select_set_distinct
Description:
Defines (if distinct is true) or removes (if distinct is
false) a DISTINCT clause for a SELECT statement.
If distinct is true, then the ID of an expression can be specified as the expr_id
argument: if not 0, this is the expression used to apply the DISTINCT clause on (the resuting SQL will then
usually be "... DISTINCT ON <expression>...").
Parameters:
| this |
a SqlBuilder object |
| distinct |
set to true to have the DISTINCT requirement |
| expr_id |
the ID of the DISTINCT ON expression, or 0 if no expression is to be used. It is ignored if |