SET Statement
Execution properties may also be set on the connection by using the SET
statement. The SET
statement is not yet a language feature of the CData Virtuality Server and is handled only in the JDBC client.
Syntax
SET [payload] (parameter|SESSION AUTHORIZATION) value
Syntax Rules
- The parameter must be a non-quoted identifier - it cannot contain spaces.
- The value may be either a non-quoted identifier or a quoted string literal value.
- If payload is specified, e.g. "
SET PAYLOAD x y
", then a session scoped payload properties object will have the corresponding name value pair set. The payload object is not fully session scoped. It will be removed from the session when the XAConnection handle is closed/returned to the pool.
The SET
statement is most commonly used to control planning and execution:
SET SHOWPLAN
(ON
|DEBUG
|OFF
)-
SET NOEXEC
(ON
|OFF
) SET
$NOOPT
(FALSE
|TRUE
)SET
$PREFER_DWH
(FORCE
|ALWAYS
|CONDITIONAL
|NEVER
)SET
$ALLOW_CARTESIAN
(NEVER
|INTERNAL
|IMPLICIT
|EXPLICIT
|ALWAYS
)
The SET
statement may also be used to control authorization; see Authorization for more information.
Options changed by the SET
statement can be overridden explicitly by the OPTION Clause.