"Christopher Kings-Lynne" <[EMAIL PROTECTED]> writes:
> Messing about with ADD COLUMN...
> I'm not certain how to re-evaluate the default expression for each
> row?
Basically you'll want to apply ExecEvalExpr (or perhaps
ExecEvalExprSwitchContext) to the "cooked" expression tree.
Look at the exec
It works very similarly to the way that ALTER TABLE ... ADD CHECK ..
works, with the tuple update added in.
Anyway, it's something like the below:
- Lock relation
- Pull out tuple
- Evaluate cooked default expression using EvalExpr
- heap_modifytuple (shove datum that EvalExpr returns into column
Hi guys,
Messing about with ADD COLUMN...
I'm not certain how to re-evaluate the default expression for each row? How
do I do this? I have access to raw_default and cooked_default it seems.
Thanks,
Chris
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