SET EXTRACT_VARIABLE#
Controls whether Querona extracts in-memory parts of a query into session variables during
preprocessing. When ON (the default), an expression that must be evaluated in memory — for example
a call such as CURRENT_USER() — is lifted into a variable and the query rewritten to reference it.
When OFF, this rewrite is skipped.
Tip
This is an advanced query-planning option, on by default. It affects only how a query is planned and executed, not its results — change it for diagnostics or to work around a specific issue.
Syntax#
SET EXTRACT_VARIABLE { ON | OFF } [;]
Remarks#
With the option on, a query such as:
SELECT CURRENT_USER();
is rewritten internally to evaluate the in-memory expression once and reuse the result:
SET @q_temp0 = CURRENT_USER();
SELECT @q_temp0;
The default is ON.
Permissions#
Requires membership in the public role.
Examples#
SET EXTRACT_VARIABLE OFF;