ASA Database Administration Guide
  Connecting to a Database
    Troubleshooting connections

Assembling a list of connection parameters

The following figure illustrates how the interface libraries assemble the list of connection parameters they use to establish a connection.

Notes 

Key points from the figure include:

• Precedence    Parameters held in more than one place are subject to the following order of precedence:

  1. Connection string

  2. SQLCONNECT

  3. Data source

That is, if a parameter is supplied both in a data source and in a connection string, the connection string value overrides the data source value.

• Failure    Failure at this stage occurs only if you specify in the connection string or in SQLCONNECT a data source that does not exist in the client connection file.

• Common parameters    Depending on other connections already in use, some connection parameters may be ignored, including:

  • AutoStop    Ignored if the database is already loaded.

  • CommLinks    The specifications for a network protocol are ignored if another connection has already set parameters for that protocol.

  • CommBufferSize    If CommBufferSize is specified on the client, the connection uses the minimum value of either the engine's buffer size or the CommBufferSize value. If it is not specified on the client, the connection uses the engine's buffer size.

  • Unconditional    Ignored if the database is already loaded or if the server is already running.

The interface library uses the completed list of connection parameters to attempt to connect.