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SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD |
java.lang.Object org.hsqldb.jdbc.jdbcConnection
A connection (session) with a specific database. Within the context of a Connection, SQL statements are executed and results are returned.
A Connection's database is able to provide information describing
its tables, its supported SQL grammar, its stored procedures, the
capabilities of this connection, and so on. This information is
obtained with the getMetaData
method.
Note: By default the Connection automatically commits changes after executing each statement. If auto commit has been disabled, an explicit commit must be done or database changes will not be saved.
To get a
Under HSQLDB, the database connection <url> must start with
'jdbc:hsqldb:'
Starting with 1.7.2, HSQLDB connection properties (<key-value-pairs>)
may be appended to the database connection <url>, using
the form:
'<url>[;key=value]*'
Starting with 1.7.2, the allowable forms of the HSQLDB database connection
<url> have been extended. However, all legacy forms continue
to work, with unchanged semantics. The extensions are as described in the
following material:
Network Server Database Connections:
The 1.7.2
The 1.7.2
In both network server database connection <url> forms, the
optional <alias> component is used to identify one of possibly
several database instances available at the indicated host and port. If the
<alias> component is omitted, then a connection is made to the
network server's default database instance (instance 0).
For more information on server configuration regarding mounting multiple
databases and assigning them <alias> values, please read the
Java API documentation for
Transient, In-Process Database Connections:
The 1.7.2 100% in-memory (transient, in-process) database connection
<url> takes one of the two following forms:
With the 1.7.2 transient, in-process database connection <url>,
the <alias> component is the key used to look up a transient,
in-process database instance amongst the collection of all such instances
already in existence within the current class loading context in the
current JVM. If no such instance exists, one may be automatically
created and mapped to the <alias>, as governed by the
'ifexists=true|false' connection property.
Persistent, In-Process Database Connections:
The 1.7.2 standalone (persistent, in-process) database connection
<url> takes one of the three following forms:
As of 1.7.2, although other files may be involved (such as transient working
files and/or TEXT table CSV data source files), the essential set that may,
at any particular point in time, compose an HSQLDB database are:
For example: 'jdbc:hsqldb:file:test' connects to a database
composed of some subset of the files listed above, where the expansion
of <path> is 'test' prefixed with the path of the
working directory fixed at the time the JVM is started.
Under Windows TM ,
'jdbc:hsqldb:file:c:\databases\test' connects a database located
on drive 'C:' in the directory 'databases', composed
of some subset of the files:
Note: Versions of HSQLDB previous to 1.7.0 did not support creating
directories along the file path specified in the persistent, in-process mode
database connection <url> form, in the case that they did
not already exist. Starting with HSQLDB 1.7.0, directories will
be created if they do not already exist., but only if HSQLDB is built under
a version of the compiler greater than JDK 1.1.x.
The new 'jdbc:hsqldb:res:<path>' database connection
<url> has different semantics than the
'jdbc:hsqldb:file:<path>' form. The semantics are similar to
those of a 'files_read_only' database, but with some additional
points to consider.
Specifically, the '<path> component of a res: type
database connection <url> is used to obtain resource URL
objects and therby read the database files as resources on the class path.
Moreover, the URL objects must point only to resources contained
in one or more jars on the class path (must be jar protocol).
In short, a res: type database connection <url> is
designed specifically to connect to a 'files_in_jar' mode database
instance, which in turn is designed specifically to operate under a
Java WebStartTM configuration,
where co-locating the database files in the jars that make up the
WebStart application avoids the need for special security
configuration or code signing.
Note: Since it is difficult or impossible to determine or control
from where classes are being loaded or which class loader is doing the
loading under 'files_in_jar' semantics, the <path>
component of the database connection <url> is always taken
to be relative to the default package. That is, if the <path>
component does not start with '/', then '/' is prepended when obtaining
the resource URLs used to read the database files.
--
For more information about HSQLDB file structure, various database modes
and other attributes such as those controlled through the HSQLDB properties
files, please read the general documentation, especially the Advanced Users
Guide.
In general, JDBC 2 support requires Java 1.2 and above, and JDBC3 requires
Java 1.4 and above. In HSQLDB, support for methods introduced in different
versions of JDBC depends on the JDK version used for compiling and building
HSQLDB.
Since 1.7.0, it is possible to build the product so that
all JDBC 2 methods can be called while executing under the version 1.1.x
Java Runtime EnvironmentTM.
However, in addition to this technique requiring explicit casts to the
org.hsqldb.jdbcXXX classes, some of the method calls also require
In a JRE 1.1.x environment, calling JDBC 2 methods that take or return the
JDBC2-only
However, please note that code written to use HSQLDB JDBC 2 features under
JDK 1.1.x will not be compatible for use with other JDBC 2 drivers. Please
also note that this feature is offered solely as a convenience to developers
who must work under JDK 1.1.x due to operating constraints, yet wish to
use some of the more advanced features available under the JDBC 2
specification.
HSQLDB-Specific Information: Connection
to an HSQLDB database, the
following code may be used (updated to reflect the most recent
recommendations):
Class c = Class.forName (
"org.hsqldb.jdbcDriver" );
Driver d = (Driver) c.newInstance();
DriverManager.registerDriver(d);
Connection c = DriverManager.getConnection
(url,user,password); Server
database connection <url> has
changed to take one of the two following forms:
WebServer
database connection <url>
also changes to take one of two following forms:
Server
and related chapters in
the general documentation, especially the Advanced Users Guide.
For the persistent, in-process database connection <url>,
the <path> component is the path prefix common to all of
the files that compose the database.
C:\
+--databases\
+--test.properties
+--test.script
+--test.log
+--test.data
+--test.backup
+--test.lck
Under most variations of UNIX, 'jdbc:hsqldb:file:/databases/test'
connects to a database located in the directory 'databases' directly
under root, once again composed of some subset of the files:
\
+--databases\
+--test.properties
+--test.script
+--test.log
+--test.data
+--test.backup
+--test.lck
Some Guidelines:
Please read your OS file system documentation.
Please read your OS file system documentation.
Please read your OS file system documentation.
JRE 1.1.x Notes: int
values that are defined only in the JDBC 2 or greater
version of
ResultSet
interface. For this reason, when the
product is compiled under JDK 1.1.x, these values are defined
in jdbcResultSet
. ResultSet
values can be achieved by referring
to them in parameter specifications and return value comparisons,
respectively, as follows:
jdbcResultSet.FETCH_FORWARD
jdbcResultSet.TYPE_FORWARD_ONLY
jdbcResultSet.TYPE_SCROLL_INSENSITIVE
jdbcResultSet.CONCUR_READ_ONLY
// etc.
(fredt@users)
(boucherb@users)
jdbcDriver
,
jdbcStatement
,
jdbcPreparedStatement
,
jdbcCallableStatement
,
jdbcResultSet
,
jdbcDatabaseMetaData
Field Summary | |
protected boolean |
isNetConn
Is this connection to a network server instance. |
Fields inherited from interface java.sql.Connection |
TRANSACTION_NONE, TRANSACTION_READ_COMMITTED, TRANSACTION_READ_UNCOMMITTED, TRANSACTION_REPEATABLE_READ, TRANSACTION_SERIALIZABLE |
Constructor Summary | |
jdbcConnection(HsqlProperties props)
Constructs a new external Connection to an HSQLDB
Database . |
|
jdbcConnection(Session c)
Constructs an INTERNAL Connection ,
using the specified Session . |
Method Summary | |
void |
clearWarnings()
Clears all warnings reported for this Connection
object. |
void |
close()
Releases this Connection
object's database and JDBC resources immediately instead of
waiting for them to be automatically released. |
void |
commit()
Makes all changes made since the previous commit/rollback permanent and releases any database locks currently held by the Connection. |
Statement |
createStatement()
Creates a Statement
object for sending SQL statements to the database. |
Statement |
createStatement(int type,
int concurrency)
Creates a Statement object that will generate
ResultSet objects with the given type and
concurrency. |
Statement |
createStatement(int resultSetType,
int resultSetConcurrency,
int resultSetHoldability)
Creates a Statement
object that will generate ResultSet objects with
the given type, concurrency, and holdability. |
void |
finalize()
The default implementation simply attempts to silently close() this Connection |
boolean |
getAutoCommit()
Gets the current auto-commit state. |
String |
getCatalog()
Returns the Connection's current catalog name. |
int |
getHoldability()
Retrieves the current holdability of ResultSet objects created using
this Connection object. |
DatabaseMetaData |
getMetaData()
Gets the metadata regarding this connection's database. |
int |
getTransactionIsolation()
Retrieves this Connection
object's current transaction isolation level. |
Map |
getTypeMap()
Gets the type map object associated with this connection. |
SQLWarning |
getWarnings()
Retrieves the first warning reported by calls on this Connection object. |
boolean |
isClosed()
Tests to see if a Connection is closed. |
boolean |
isReadOnly()
Tests to see if the connection is in read-only mode. |
String |
nativeSQL(String sql)
Converts the given SQL statement into the system's native SQL grammar. |
CallableStatement |
prepareCall(String sql)
Creates a CallableStatement
object for calling database stored procedures. |
CallableStatement |
prepareCall(String sql,
int resultSetType,
int resultSetConcurrency)
Creates a CallableStatement
object that will generate ResultSet objects with
the given type and concurrency. |
CallableStatement |
prepareCall(String sql,
int resultSetType,
int resultSetConcurrency,
int resultSetHoldability)
Creates a CallableStatement
object that will generate ResultSet objects with
the given type and concurrency. |
PreparedStatement |
prepareStatement(String sql)
Creates a PreparedStatement
object for sending parameterized SQL statements to the
database. |
PreparedStatement |
prepareStatement(String sql,
int autoGeneratedKeys)
Creates a default PreparedStatement
object that has the capability to retrieve auto-generated
keys. |
PreparedStatement |
prepareStatement(String sql,
int[] columnIndexes)
Creates a default PreparedStatement
object capable of returning the auto-generated keys designated
by the given array. |
PreparedStatement |
prepareStatement(String sql,
int type,
int concurrency)
Creates a PreparedStatement object that will
generate ResultSet objects with the given type
and concurrency. |
PreparedStatement |
prepareStatement(String sql,
int resultSetType,
int resultSetConcurrency,
int resultSetHoldability)
Creates a PreparedStatement
object that will generate ResultSet objects with
the given type, concurrency, and holdability. |
PreparedStatement |
prepareStatement(String sql,
String[] columnNames)
Creates a default PreparedStatement
object capable of returning the auto-generated keys designated
by the given array. |
void |
releaseSavepoint(Savepoint savepoint)
Removes the given Savepoint
object from the current transaction. |
void |
rollback()
Drops all changes made since the previous commit/rollback and releases any database locks currently held by this Connection. |
void |
rollback(Savepoint savepoint)
Undoes all changes made after the given Savepoint object was set. |
void |
setAutoCommit(boolean autoCommit)
Sets this connection's auto-commit mode to the given state. |
void |
setCatalog(String catalog)
Sets a catalog name in order to select a subspace of this Connection's database in which to work. |
void |
setHoldability(int holdability)
Changes the holdability of ResultSet objects created using this
Connection object to the given holdability. |
void |
setReadOnly(boolean readonly)
Puts this connection in read-only mode as a hint to enable database optimizations. |
Savepoint |
setSavepoint()
Creates an unnamed savepoint in the current transaction and returns the new Savepoint
object that represents it. |
Savepoint |
setSavepoint(String name)
Creates a savepoint with the given name in the current transaction and returns the new Savepoint object that represents it. |
void |
setTransactionIsolation(int level)
Attempts to change the transaction isolation level for this Connection object to the one given. |
void |
setTypeMap(Map map)
Installs the given TypeMap
object as the type map for this Connection
object. |
Methods inherited from class java.lang.Object |
clone, equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
Field Detail |
protected boolean isNetConn
Constructor Detail |
public jdbcConnection(HsqlProperties props) throws SQLException
Connection
to an HSQLDB
Database
.
This constructor is called on behalf of the
java.sql.DriverManager
when getting a
Connection
for use in normal (external)
client code.
Internal client code, that being code located in HSQLDB SQL
functions and stored procedures, receives an INTERNAL
connection constructed by the jdbcConnection(Session)
constructor.
props
- A Properties
object containing the connection
properties
SQLException
- when the user/password combination is
invalid, the connection url is invalid, or the
Database
is unavailable.
The Database
may be unavailable for a number
of reasons, including network problems or the fact that it
may already be in use by another process.
public jdbcConnection(Session c) throws HsqlException
INTERNAL
Connection
,
using the specified Session
.
This constructor is called only on behalf of an existing
Session
(the internal parallel of a
Connection
), to be used as a parameter to a SQL
function or stored procedure that needs to execute in the context
of that Session
.
When a Java SQL function or stored procedure is called and its
first parameter is of type Connection
, HSQLDB
automatically notices this and constructs an INTERNAL
Connection
using the current Session
.
HSQLDB then passes this Connection
in the first
parameter position, moving any other parameter values
specified in the SQL statement to the right by one position.
To read more about this, see Function#getValue()
.
Notes:
Starting with HSQLDB 1.7.2, INTERNAL
connections are not
closed by a call to close() or by a SQL DISCONNECT.
For HSQLDB developers not involved with writing database
internals, this change only applies to connections obtained
automatically from the database as the first parameter to
stored procedures and SQL functions. This is mainly an issue
to developers writing custom SQL function and stored procedure
libraries for HSQLDB. Presently, it is recommended that SQL function and
stored procedure code avoid depending on closing or issuing a
DISCONNECT on a connection obtained in this manner.
c
- the Session requesting the construction of this
Connection
HsqlException
- never (reserved for future use);Function
Method Detail |
public Statement createStatement() throws SQLException
Statement
object for sending SQL statements to the database. SQL
statements without parameters are normally executed using
Statement
objects. If the same SQL statement is
executed many times, it may be more efficient to use a
PreparedStatement
object.
Result sets created using the returned Statement
object will by default be type TYPE_FORWARD_ONLY
and have a concurrency level of CONCUR_READ_ONLY
.
HSQLDB-Specific Information:
Starting with HSQLDB 1.7.2, support for precompilation at the engine level
has been implemented, so it is now much more efficient and performant
to use a
Up to 1.6.1, HSQLDB supported
Starting with 1.7.0, HSQLDB also supports
Notes:
Up to 1.6.1, calling this method returned
PreparedStatement
object if the same SQL statement
is executed many times. TYPE_FORWARD_ONLY
-
CONCUR_READ_ONLY
results only, so ResultSet
objects created using the returned Statement
object would always be type TYPE_FORWARD_ONLY
with CONCUR_READ_ONLY
concurrency. TYPE_SCROLL_INSENSITIVE
results. null
if the
connection was already closed. This was possibly counter-intuitive
to the expectation that an exception would be thrown for
closed connections. Starting with 1.7.0. the behaviour is to throw a
SQLException
if the connection is closed.
createStatement
in interface Connection
SQLException
- if a database access error occurscreateStatement(int,int)
,
createStatement(int,int,int)
public PreparedStatement prepareStatement(String sql) throws SQLException
PreparedStatement
object for sending parameterized SQL statements to the
database.
A SQL statement with or without IN parameters can be
pre-compiled and stored in a PreparedStatement
object. This object can then be used to efficiently execute
this statement multiple times.
Note: This method is optimized for handling parametric
SQL statements that benefit from precompilation. If the driver
supports precompilation, the method prepareStatement
will send the statement to the database for precompilation.
Some drivers may not support precompilation. In this case, the
statement may not be sent to the database until the
PreparedStatement
object is executed. This has no
direct effect on users; however, it does affect which methods
throw certain SQLException
objects.
Result sets created using the returned PreparedStatement
object will by default be type TYPE_FORWARD_ONLY
and have a concurrency level of CONCUR_READ_ONLY
.
HSQLDB-Specific Information:
Starting with HSQLDB 1.7.2, support for precompilation at the engine level
has been implemented, so it is now much more efficient and performant
to use a
Starting with 1.7.2, the support for and behaviour of
PreparedStatment has changed. Please read the introductory section
of the documentation for org.hsqldb.jdbcPreparedStatement.
PreparedStatement
object if the same SQL statement
is executed many times.
prepareStatement
in interface Connection
sql
- an SQL statement that may contain one or more '?'
IN parameter placeholders
PreparedStatement
object
containing the pre-compiled SQL statement
SQLException
- if a database access error occurs prepareStatement(String,int,int)
public CallableStatement prepareCall(String sql) throws SQLException
CallableStatement
object for calling database stored procedures. The
CallableStatement
object provides methods for setting up
its IN and OUT parameters, and methods for executing the call to a
stored procedure.
Note: This method is optimized for handling stored
procedure call statements. Some drivers may send the call
statement to the database when the method prepareCall
is done; others may wait until the CallableStatement
object is executed. This has no direct effect on users;
however, it does affect which method throws certain
SQLExceptions.
Result sets created using the returned CallableStatement
object will by default be type TYPE_FORWARD_ONLY
and have a concurrency level of CONCUR_READ_ONLY
.
HSQLDB-Specific Information:
Starting with 1.7.2, the support for and behaviour of
CallableStatement has changed. Please read the introductory section
of the documentation for org.hsqldb.jdbcCallableStatement.
prepareCall
in interface Connection
sql
- a String object that is the SQL statement to be
sent to the database; may contain one or more ?
parameters. Note: Typically the SQL statement is a JDBC function call escape string.
CallableStatement
object
containing the pre-compiled SQL statement
SQLException
- if a database access error occurs prepareCall(String,int,int)
public String nativeSQL(String sql) throws SQLException
HSQLDB-Specific Information:
Up to and including 1.7.2, HSQLDB converts the JDBC SQL
grammar into the system's native SQL grammar prior to sending
it, if escape processing is set true; this method returns the
native form of the statement that the driver would send in place
of client-specified JDBC SQL grammar.
Before 1.7.2, escape processing was incomplete and
also broken in terms of support for nested escapes.
Starting with 1.7.2, escape processing is complete and handles nesting
to arbitrary depth, but enforces a very strict interpretation of the
syntax and does not detect or process SQL comments.
In essence, the HSQLDB engine directly handles the prescribed syntax
and date / time formats specified internal to the JDBC escapes.
It also directly offers the XOpen / ODBC extended scalar
functions specified available internal to the {fn ...} JDBC escape.
As such, the driver simply removes the curly braces and JDBC escape
codes in the simplest and fastest fashion possible, by replacing them
with whitespace.
But to avoid a great deal of complexity, certain forms of input
whitespace are currently not recognised. For instance,
the driver handles "{?= call ...}" but not "{ ?= call ...} or
"{? = call ...}"
Also, comments embedded in SQL are currently not detected or
processed and thus may have unexpected effects on the output
of this method, for instance causing otherwise valid SQL to become
invalid. It is especially important to be aware of this because escape
processing is set true by default for Statement objects and is always
set true when producing a PreparedStatement from prepareStatement()
or CallableStatement from prepareCall(). Currently, it is simply
recommended to avoid submitting SQL having comments containing JDBC
escape sequence patterns and/or single or double quotation marks,
as this will avoid any potential problems.
It is intended to implement a less strict handling of whitespace and
proper processing of SQL comments at some point in the near future,
perhaps before the final 1.7.2 release.
In any event, 1.7.2 now correctly processes the following JDBC escape
forms to arbitrary nesting depth, but only if the exact whitespace
layout described below is used:
nativeSQL
in interface Connection
sql
- a SQL statement that may contain one or more '?'
parameter placeholders
SQLException
- if a database access error occurs public void setAutoCommit(boolean autoCommit) throws SQLException
commit
or
the method rollback
. By default, new connections are
in auto-commit mode.
The commit occurs when the statement completes or the next
execute occurs, whichever comes first. In the case of
statements returning a ResultSet
object, the
statement completes when the last row of the ResultSet
object has been retrieved or the ResultSet
object
has been closed. In advanced cases, a single statement may
return multiple results as well as output parameter values. In
these cases, the commit occurs when all results and output
parameter values have been retrieved.
NOTE: If this method is called during a transaction, the transaction is committed.
HSQLDB-Specific Information:
Up to and including HSQLDB 1.7.2,
(boucherb@users)
Therefore, a statement can be considered complete as soon as
any XXXStatement.executeXXX method returns.
setAutoCommit
in interface Connection
autoCommit
- true
to enable auto-commit
mode; false
to disable it
SQLException
- if a database access error occursgetAutoCommit()
public boolean getAutoCommit() throws SQLException
getAutoCommit
in interface Connection
SQLException
- Description of the ExceptionsetAutoCommit(boolean)
public void commit() throws SQLException
HSQLDB-Specific Information:
Starting with HSQLDB 1.7.2, savepoints are supported both
in SQL and via the JDBC interface.
Using SQL, savepoints may be set, released and used in rollback
as follows:
SAVEPOINT <savepoint-name>
RELEASE SAVEPOINT <savepoint-name>
ROLLBACK TO SAVEPOINT <savepoint-name>
commit
in interface Connection
SQLException
- if a database access error occurssetAutoCommit(boolean)
public void rollback() throws SQLException
HSQLDB-Specific Information:
Starting with HSQLDB 1.7.2, savepoints are fully supported both
in SQL and via the JDBC interface.
Using SQL, savepoints may be set, released and used in rollback
as follows:
SAVEPOINT <savepoint-name>
RELEASE SAVEPOINT <savepoint-name>
ROLLBACK TO SAVEPOINT <savepoint-name>
rollback
in interface Connection
SQLException
- if a database access error occurssetAutoCommit(boolean)
public void close() throws SQLException
Connection
object's database and JDBC resources immediately instead of
waiting for them to be automatically released.
Calling the method close
on a Connection
object that is already closed is a no-op.
Note: A Connection
object is automatically
closed when it is garbage collected. Certain fatal errors also
close a Connection
object.
HSQLDB-Specific Information:
In 1.7.2,
INTERNAL
Connection
objects are not closable from JDBC client code.
close
in interface Connection
SQLException
- if a database access error occurspublic boolean isClosed()
isClosed
in interface Connection
public DatabaseMetaData getMetaData() throws SQLException
DatabaseMetaData
object.
HSQLDB-Specific Information:
JDBC
Also, the majority of methods returning
For discussion in greater detail, please follow the link to the
overview for jdbcDatabaseMetaData, below.
DatabaseMetaData
methods returning
ResultSet
were not implemented fully before 1.7.2.
Some of these methods always returned empty result sets.
Other methods did not accurately
reflect all of the MetaData for the category.
Also, some method ignored the filters provided as
parameters, returning an unfiltered result each time. ResultSet
threw an SQLException
when accessed by a non-admin
user.
Starting with HSQLDB 1.7.2, essentially full database metadata
is supported.
getMetaData
in interface Connection
SQLException
- if a database access error occursjdbcDatabaseMetaData
public void setReadOnly(boolean readonly) throws SQLException
Note: This method should not be called while in the middle of a transaction.
HSQLDB-Specific Information:
Up to and including 1.7.2, HSQLDB will commit the current
transaction automatically when this method is called.
Additionally, HSQLDB provides a way to put a whole database in
read-only mode. This is done by manually adding the line
'readonly=true' to the database's .properties file while the
database is offline. Upon restart, all connections will be
readonly, since the entire database will be readonly. To take
a database out of readonly mode, simply take the database
offline and remove the line 'readonly=true' from the
database's .properties file. Upon restart, the database will
be in regular (read-write) mode.
When a database is put in readonly mode, its files are opened
in readonly mode, making it possible to create CD-based
readonly databases. To create a CD-based readonly database
that has CACHED tables and whose .data file is suspected of
being highly fragmented, it is recommended that the database
first be SHUTDOWN COMPACTed before copying the database
files to CD. This will reduce the space required and may
improve access times against the .data file which holds the
CACHED table data.
Starting with 1.7.2, an alternate approach to opimizing the
.data file before creating a CD-based readonly database is to issue
the CHECKPOINT DEFRAG command followed by SHUTDOWN to take the
database offline in preparation to burn the database files to CD.
setReadOnly
in interface Connection
readonly
- The new readOnly value
SQLException
- if a database access error occurspublic boolean isReadOnly() throws SQLException
isReadOnly
in interface Connection
SQLException
- if a database access error occurspublic void setCatalog(String catalog) throws SQLException
HSQLDB-Specific Information:
HSQLDB does not yet support catalogs and simply ignores this
request.
setCatalog
in interface Connection
catalog
- the name of a catalog (subspace in this
Connection object's database) in which to work (Ignored)
SQLException
- if a database access error occurs public String getCatalog() throws SQLException
HSQLDB-Specific Information:
HSQLDB does not yet support catalogs and always returns null.
getCatalog
in interface Connection
For HSQLDB, this is always null.
SQLException
- Description of the Exceptionpublic void setTransactionIsolation(int level) throws SQLException
Connection
object to the one given. The constants
defined in the interface Connection
are the
possible transaction isolation levels. Note: If this method is called during a transaction, the result is implementation-defined.
HSQLDB-Specific Information:
Up to and including 1.7.1, HSQLDB supports only
Connection.TRANSACTION_READ_UNCOMMITTED
.
setTransactionIsolation
in interface Connection
level
- one of the following Connection
constants: Connection.TRANSACTION_READ_UNCOMMITTED
, Connection.TRANSACTION_READ_COMMITTED
,
Connection.TRANSACTION_REPEATABLE_READ
, or
Connection.TRANSACTION_SERIALIZABLE
. (Note
that Connection.TRANSACTION_NONE
cannot be
used because it specifies that transactions are not
supported.)
SQLException
- if a database access error occurs or
the given parameter is not one of the Connection
constants jdbcDatabaseMetaData.supportsTransactionIsolationLevel(int)
,
getTransactionIsolation()
public int getTransactionIsolation() throws SQLException
Connection
object's current transaction isolation level.
HSQLDB-Specific Information:
HSQLDB always returns
Connection.TRANSACTION_READ_UNCOMMITED
.
getTransactionIsolation
in interface Connection
Connection.TRANSACTION_READ_UNCOMMITTED
, Connection.TRANSACTION_READ_COMMITTED
,
Connection.TRANSACTION_REPEATABLE_READ
,
Connection.TRANSACTION_SERIALIZABLE
, or
Connection.TRANSACTION_NONE
Up to and including 1.7.1, TRANSACTION_READ_UNCOMMITTED is always returned
SQLException
- if a database access error occurs jdbcDatabaseMetaData.supportsTransactionIsolationLevel(int)
,
setTransactionIsolation
public SQLWarning getWarnings() throws SQLException
Connection
object. If there is more than one
warning, subsequent warnings will be chained to the first
one and can be retrieved by calling the method
SQLWarning.getNextWarning
on the warning
that was retrieved previously.
This method may not be called on a closed connection; doing so
will cause an SQLException
to be thrown.
Note: Subsequent warnings will be chained to this SQLWarning.
HSQLDB-Specific Information:
Starting with 1.7.2, HSQLDB produces warnings whenever a createStatement(),
prepareStatement() or prepareCall() invocation requests an unsupported
but defined combination of result set type, concurrency and holdability,
such that another set is substituted.
getWarnings
in interface Connection
SQLWarning
object or null
if there are none
SQLException
- if a database access error occurs or
this method is called on a closed connection SQLWarning
public void clearWarnings() throws SQLException
Connection
object. After a call to this method, the method
getWarnings
returns null until
a new warning is reported for this Connection.
HSQLDB-Specific Information:
Before HSQLDB 1.7.2,
Starting with HSQLDB 1.7.2, the standard behaviour is implemented.
SQLWarning
was not
supported, and calls to this method are simply ignored.
clearWarnings
in interface Connection
SQLException
- if a database access error occurs public Statement createStatement(int type, int concurrency) throws SQLException
Statement
object that will generate
ResultSet
objects with the given type and
concurrency. This method is the same as the
createStatement
method above, but it allows the
default result set type and result set concurrency type to be
overridden.
HSQLDB-Specific Information:
Up to HSQLDB 1.6.1, support was provided only for type
Starting with HSQLDB 1.7.0, support is now provided for types
Notes:
Up to 1.6.1, calling this method returned
TYPE_FORWARD_ONLY
and concurrency CONCUR_READ_ONLY
. TYPE_FORWARD_ONLY
, and
TYPE_SCROLL_INSENSITIVE
,
with concurrency CONCUR_READ_ONLY
.
Starting with HSQLDB 1.7.2, the behaviour regarding the type and
concurrency values has changed to more closely conform to the
specification. That is, if an unsupported combination is requested,
a SQLWarning is issued on this Connection and the closest supported
combination is used instead. null
if the
connection was already closed and a supported combination of type and
concurrency was specified. This was possibly counter-intuitive
to the expectation that an exception would be thrown for
closed connections. Starting with 1.7.0. the behaviour is to throw a
SQLException
if the connection is closed.
createStatement
in interface Connection
type
- a result set type; one of
ResultSet.TYPE_FORWARD_ONLY
,
ResultSet.TYPE_SCROLL_INSENSITIVE
, or
ResultSet.TYPE_SCROLL_SENSITIVE
(not
supported)concurrency
- a concurrency type; one of
ResultSet.CONCUR_READ_ONLY
or ResultSet.CONCUR_UPDATABLE
(not supported)
Statement
object that will, within
the release-specific documented limitations of support,
generate ResultSet
objects with the given
type and concurrency
SQLException
- if a database access error occurs or
the given parameters are not ResultSet constants
indicating a supported type and concurrencypublic PreparedStatement prepareStatement(String sql, int type, int concurrency) throws SQLException
PreparedStatement
object that will
generate ResultSet
objects with the given type
and concurrency. This method is the same as the
prepareStatement
method above, but it allows the
default result set type and result set concurrency type to be
overridden.
HSQLDB-Specific Information:
Starting with HSQLDB 1.7.2, the behaviour regarding the type and
concurrency values has changed to more closely conform to the
specification. That is, if an unsupported combination is requested,
a SQLWarning is issued on this Connection and the closest supported
combination is used instead.
Also starting with 1.7.2, the support for and behaviour of
PreparedStatment has changed. Please read the introductory section
of the documentation for org.hsqldb.jdbcPreparedStatement.
prepareStatement
in interface Connection
sql
- a String object that is the SQL statement to be
sent to the database; may contain one or more ? IN
parameterstype
- a result set type; one of
ResultSet.TYPE_FORWARD_ONLY
,
ResultSet.TYPE_SCROLL_INSENSITIVE
, or
ResultSet.TYPE_SCROLL_SENSITIVE
(not
supported)concurrency
- a concurrency type; one of
ResultSet.CONCUR_READ_ONLY
or ResultSet.CONCUR_UPDATABLE
(not supported)
ResultSet
objects with the given type and concurrency
SQLException
- if a database access error occurs or
the given parameters are not ResultSet constants
indicating a supported type and concurrencypublic CallableStatement prepareCall(String sql, int resultSetType, int resultSetConcurrency) throws SQLException
CallableStatement
object that will generate ResultSet
objects with
the given type and concurrency. This method is the same as the
prepareCall
method above, but it allows the
default result set type and result set concurrency type to be
overridden.
HSQLDB-Specific Information:
Starting with HSQLDB 1.7.2, the behaviour regarding the type,
concurrency and holdability values has changed to more closely
conform to the specification. That is, if an unsupported
combination is requrested, a SQLWarning is issued on this Connection
and the closest supported combination is used instead.
Also starting with 1.7.2, the support for and behaviour of
CallableStatement has changed. Please read the introdutory section
of the documentation for org.hsqldb.jdbcCallableStatement.
prepareCall
in interface Connection
sql
- a String object that is the SQL statement to be
sent to the database; may contain one or more ? parametersresultSetType
- a result set type; one of
ResultSet.TYPE_FORWARD_ONLY
,
ResultSet.TYPE_SCROLL_INSENSITIVE
, (not
supported) or ResultSet.TYPE_SCROLL_SENSITIVE
(not supported)resultSetConcurrency
- a concurrency type; one of
ResultSet.CONCUR_READ_ONLY
or ResultSet.CONCUR_UPDATABLE
(not supported)
SQLException
- if a database access error occurs or
the given parameters are not ResultSet
constants indicating a supported type and concurrencypublic Map getTypeMap() throws SQLException
HSQLDB-Specific Information:
HSQLDB 1.7.2 does not support this feature. Calling this
method always throws a
SQLException
, stating that the
function is not supported.
getTypeMap
in interface Connection
java.util.Map
object associated with
this Connection
object
SQLException
- if a database access error occurs
(always, up to HSQLDB 1.7.0, inclusive)public void setTypeMap(Map map) throws SQLException
TypeMap
object as the type map for this Connection
object. The type map will be used for the custom mapping of
SQL structured types and distinct types.
HSQLDB-Specific Information:
HSQLDB 1.7.2 does not support this feature. Calling this
method always throws a
SQLException
, stating that
the function is not supported.
setTypeMap
in interface Connection
map
- the java.util.Map
object to install as
the replacement for this Connection
object's
default type map
SQLException
- if a database access error occurs or
the given parameter is not a java.util.Map
object (always, up to HSQLDB 1.7.0, inclusive)getTypeMap()
public void setHoldability(int holdability) throws SQLException
ResultSet
objects created using this
Connection
object to the given holdability.
HSQLDB-Specific Information:
Starting with HSQLDB 1.7.2, this feature is supported.
As of 1.7.2, only HOLD_CURSORS_OVER_COMMIT is supported; supplying
any other value will throw an exception.
setHoldability
in interface Connection
holdability
- a ResultSet
holdability
constant; one of ResultSet.HOLD_CURSORS_OVER_COMMIT
or ResultSet.CLOSE_CURSORS_AT_COMMIT
SQLException
- if a database access occurs, the given
parameter is not a ResultSet
constant
indicating holdability, or the given holdability is not
supportedgetHoldability()
,
ResultSet
public int getHoldability() throws SQLException
ResultSet
objects created using
this Connection
object.
HSQLDB-Specific Information:
Starting with HSQLDB 1.7.2, this feature is supported.
Calling this method always returns HOLD_CURSORS_OVER_COMMIT.
getHoldability
in interface Connection
ResultSet.HOLD_CURSORS_OVER_COMMIT
or ResultSet.CLOSE_CURSORS_AT_COMMIT
SQLException
- if a database access occurssetHoldability(int)
,
ResultSet
public Savepoint setSavepoint() throws SQLException
Savepoint
object that represents it.
HSQLDB-Specific Information:
HSQLDB 1.7.2 does not support this feature.
Calling this method always throws a
SQLException
,
stating that the function is not supported.
setSavepoint
in interface Connection
Savepoint
object
SQLException
- if a database access error occurs or
this Connection
object is currently in
auto-commit modejdbcSavepoint
,
Savepoint
public Savepoint setSavepoint(String name) throws SQLException
Savepoint
object that represents it.
HSQLDB-Specific Information:
setSavepoint
in interface Connection
name
- a String
containing the name of the savepoint
Savepoint
object
SQLException
- if a database access error occurs or
this Connection
object is currently in
auto-commit modejdbcSavepoint
,
Savepoint
public void rollback(Savepoint savepoint) throws SQLException
Savepoint
object was set. This method should be used only when auto-commit has been disabled.
HSQLDB-Specific Information:
rollback
in interface Connection
savepoint
- the Savepoint
object to roll back to
SQLException
- if a database access error occurs,
the Savepoint
object is no longer valid,
or this Connection
object is currently in
auto-commit modejdbcSavepoint
,
Savepoint
,
rollback()
public void releaseSavepoint(Savepoint savepoint) throws SQLException
Savepoint
object from the current transaction. Any reference to the
savepoint after it have been removed will cause an
SQLException
to be thrown.
HSQLDB-Specific Information:
releaseSavepoint
in interface Connection
savepoint
- the Savepoint
object to be removed
SQLException
- if a database access error occurs or
the given Savepoint
object is not a valid
savepoint in the current transactionjdbcSavepoint
,
Savepoint
public Statement createStatement(int resultSetType, int resultSetConcurrency, int resultSetHoldability) throws SQLException
Statement
object that will generate ResultSet
objects with
the given type, concurrency, and holdability. This method is
the same as the createStatement
method above, but
it allows the default result set type, concurrency, and
holdability to be overridden.
HSQLDB-Specific Information:
Starting with HSQLDB 1.7.2, this feature is supported.
Starting with HSQLDB 1.7.2, the behaviour regarding the type,
concurrency and holdability values has changed to more closely conform
to the specification. That is, if an unsupported combination is requested,
a SQLWarning is issued on this Connection and the closest supported
combination is used instead.
createStatement
in interface Connection
resultSetType
- one of the following ResultSet
constants: ResultSet.TYPE_FORWARD_ONLY
,
ResultSet.TYPE_SCROLL_INSENSITIVE
,
or ResultSet.TYPE_SCROLL_SENSITIVE
resultSetConcurrency
- one of the following
ResultSet
constants: ResultSet.CONCUR_READ_ONLY
or
ResultSet.CONCUR_UPDATABLE
resultSetHoldability
- one of the following
code>ResultSet
constants: ResultSet.HOLD_CURSORS_OVER_COMMIT
or ResultSet.CLOSE_CURSORS_AT_COMMIT
Statement
object that will generate
ResultSet
objects with the given type,
concurrency, and holdability
SQLException
- if a database access error occurs or
the given parameters are not ResultSet
constants indicating type, concurrency, and holdabilityResultSet
public PreparedStatement prepareStatement(String sql, int resultSetType, int resultSetConcurrency, int resultSetHoldability) throws SQLException
PreparedStatement
object that will generate ResultSet
objects with
the given type, concurrency, and holdability.
This method is the same as the prepareStatement
method above, but it allows the default result set type,
concurrency, and holdability to be overridden.
HSQLDB-Specific Information:
Starting with HSQLDB 1.7.2, this feature is supported.
Starting with HSQLDB 1.7.2, the behaviour regarding the type,
concurrency and holdability values has changed to more closely
conform to the specification. That is, if an unsupported
combination is requested, a SQLWarning is issued on this Connection
and the closest supported combination is used instead.
Also starting with 1.7.2, the support for and behaviour of
PreparedStatment has changed. Please read the introductory section
of the documentation for org.hsqldb.jdbcPreparedStatement.
prepareStatement
in interface Connection
sql
- a String
object that is the SQL
statement to be sent to the database; may contain one or
more ? IN parametersresultSetType
- one of the following ResultSet
constants: ResultSet.TYPE_FORWARD_ONLY
,
ResultSet.TYPE_SCROLL_INSENSITIVE
,
or ResultSet.TYPE_SCROLL_SENSITIVE
resultSetConcurrency
- one of the following
ResultSet
constants: ResultSet.CONCUR_READ_ONLY
or
ResultSet.CONCUR_UPDATABLE
resultSetHoldability
- one of the following
ResultSet
constants: ResultSet.HOLD_CURSORS_OVER_COMMIT
or ResultSet.CLOSE_CURSORS_AT_COMMIT
PreparedStatement
object,
containing the pre-compiled SQL statement, that will
generate ResultSet
objects with the given
type, concurrency, and holdability
SQLException
- if a database access error occurs or
the given parameters are not ResultSet
constants indicating type, concurrency, and holdabilityResultSet
public CallableStatement prepareCall(String sql, int resultSetType, int resultSetConcurrency, int resultSetHoldability) throws SQLException
CallableStatement
object that will generate ResultSet
objects with
the given type and concurrency. This method is the same as the
prepareCall
method above, but it allows the
default result set type, result set concurrency type and
holdability to be overridden.
HSQLDB-Specific Information:
Starting with HSQLDB 1.7.2, this feature is supported.
Starting with HSQLDB 1.7.2, the behaviour regarding the type,
concurrency and holdability values has changed to more closely
conform to the specification. That is, if an unsupported
combination is requrested, a SQLWarning is issued on this Connection
and the closest supported combination is used instead.
Also starting with 1.7.2, the support for and behaviour of
CallableStatment has changed. Please read the introdutory section
of the documentation for org.hsqldb.jdbcCallableStatement.
prepareCall
in interface Connection
sql
- a String
object that is the SQL
statement to be sent to the database; may contain on or
more ? parametersresultSetType
- one of the following ResultSet
constants: ResultSet.TYPE_FORWARD_ONLY
,
ResultSet.TYPE_SCROLL_INSENSITIVE
, or
ResultSet.TYPE_SCROLL_SENSITIVE
resultSetConcurrency
- one of the following
ResultSet
constants: ResultSet.CONCUR_READ_ONLY
or
ResultSet.CONCUR_UPDATABLE
resultSetHoldability
- one of the following
ResultSet
constants: ResultSet.HOLD_CURSORS_OVER_COMMIT
or ResultSet.CLOSE_CURSORS_AT_COMMIT
CallableStatement
object,
containing the pre-compiled SQL statement, that will
generate ResultSet
objects with the given
type, concurrency, and holdability
SQLException
- if a database access error occurs or
the given parameters are not ResultSet
constants indicating type, concurrency, and holdabilityResultSet
public PreparedStatement prepareStatement(String sql, int autoGeneratedKeys) throws SQLException
PreparedStatement
object that has the capability to retrieve auto-generated
keys. The given constant tells the driver whether it should
make auto-generated keys available for retrieval. This
parameter is ignored if the SQL statement is not an
INSERT
statement.
Note: This method is optimized for handling parametric
SQL statements that benefit from precompilation. If the driver
supports precompilation, the method prepareStatement
will send the statement to the database for precompilation.
Some drivers may not support precompilation. In this case, the
statement may not be sent to the database until the
PreparedStatement
object is executed. This has no direct effect on users;
however, it does affect which methods throw certain
SQLExceptions.
Result sets created using the returned PreparedStatement
object will by default be type TYPE_FORWARD_ONLY
and have a concurrency level of CONCUR_READ_ONLY
.
HSQLDB-Specific Information:
HSQLDB 1.7.2 does not support this feature.
Calling this method always throws a
SQLException
,
stating that the function is not supported.
prepareStatement
in interface Connection
sql
- an SQL statement that may contain one or more '?'
IN parameter placeholdersautoGeneratedKeys
- a flag indicating that auto-generated
keys should be returned, one of
code>Statement.RETURN_GENERATED_KEYS
or Statement.NO_GENERATED_KEYS
.
PreparedStatement
object,
containing the pre-compiled SQL statement, that will have
the capability of returning auto-generated keys
SQLException
- if a database access error occurs or
the given parameter is not a Statement
constant indicating whether auto-generated keys should be
returnedpublic PreparedStatement prepareStatement(String sql, int[] columnIndexes) throws SQLException
PreparedStatement
object capable of returning the auto-generated keys designated
by the given array. This array contains the indexes of the
columns in the target table that contain the auto-generated
keys that should be made available. This array is ignored if
the SQL statement is not an INSERT
statement.
An SQL statement with or without IN parameters can be
pre-compiled and stored in a PreparedStatement
object. This object can then be used to efficiently execute
this statement multiple times.
Note: This method is optimized for handling parametric
SQL statements that benefit from precompilation. If the driver
supports precompilation, the method prepareStatement
will send the statement to the database for precompilation.
Some drivers may not support precompilation. In this case, the
statement may not be sent to the database until the
PreparedStatement
object is executed. This has no direct effect on users;
however, it does affect which methods throw certain
SQLExceptions.
Result sets created using the returned PreparedStatement
object will by default be type TYPE_FORWARD_ONLY
and have a concurrency level of CONCUR_READ_ONLY
.
HSQLDB-Specific Information:
HSQLDB 1.7.2 does not support this feature.
Calling this method always throws a
SQLException
,
stating that the function is not supported.
prepareStatement
in interface Connection
sql
- an SQL statement that may contain one or more '?'
IN parameter placeholderscolumnIndexes
- an array of column indexes indicating the
columns that should be returned from the inserted row or
rows
PreparedStatement
object,
containing the pre-compiled statement, that is capable of
returning the auto-generated keys designated by the given
array of column indexes
SQLException
- if a database access error occurspublic PreparedStatement prepareStatement(String sql, String[] columnNames) throws SQLException
PreparedStatement
object capable of returning the auto-generated keys designated
by the given array. This array contains the names of the
columns in the target table that contain the auto-generated
keys that should be returned. This array is ignored if the SQL
statement is not an INSERT
statement.
An SQL statement with or without IN parameters can be
pre-compiled and stored in a PreparedStatement
object. This object can then be used to efficiently execute
this statement multiple times.
Note: This method is optimized for handling parametric
SQL statements that benefit from precompilation. If the driver
supports precompilation, the method prepareStatement
will send the statement to the database for precompilation.
Some drivers may not support precompilation. In this case, the
statement may not be sent to the database until the
PreparedStatement
object is executed. This has no direct effect on users;
however, it does affect which methods throw certain
SQLExceptions.
Result sets created using the returned PreparedStatement
object will by default be type TYPE_FORWARD_ONLY
and have a concurrency level of CONCUR_READ_ONLY
.
HSQLDB-Specific Information:
HSQLDB 1.7.2 does not support this feature.
Calling this method always throws a
SQLException
,
stating that the function is not supported.
prepareStatement
in interface Connection
sql
- an SQL statement that may contain one or more '?'
IN parameter placeholderscolumnNames
- an array of column names indicating the
columns that should be returned from the inserted row or
rows
PreparedStatement
object,
containing the pre-compiled statement, that is capable of
returning the auto-generated keys designated by the given
array of column names
SQLException
- if a database access error occurspublic void finalize()
close()
this Connection
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