Contents Index Subquery allowed only one select list item Subscription to '%1' for '%2' already exists

ASA Error Messages
  Database Error Messages
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Subquery cannot return more than one row

Item Value
SQLCODE -186
Constant SQLE_SUBQUERY_RESULT_NOT_UNIQUE
SQLSTATE 21W01
Sybase error code 512
ODBC 2 State 37000
ODBC 3 State 42000
Probable cause 

You used a subquery that returns more than one row, in a context where only a single row can be used. If the subquery is in the WHERE clause, you might be able to use the IN keyword.

Contents Index Subquery allowed only one select list item Subscription to '%1' for '%2' already exists