Re: patch: function xmltable

Pavel Stehule wrote:

> 2016-12-02 23:25 GMT+01:00 Alvaro Herrera <alvherre(at)2ndquadrant(dot)com>:

> > This is looking much better now, but it still needs at least the
> > following changes.
> >
> > First, we need to fix is the per_rowset_memcxt thingy. I think the way
> > it's currently being used is rather ugly; it looks to me like the memory
> > context does not belong into the XmlTableContext struct at all.
> > Instead, the executor code should keep the memcxt pointer in a state
> > struct of its own, and it should be the executor's responsibility to
> > change to the appropriate context before calling the table builder
> > functions. In particular, this means that the table context can no
> > longer be a void * pointer; it needs to be a struct that's defined by
> > the executor (probably a primnodes.h one). The void * pointer is
> > stashed inside that struct. Also, the "routine" pointer should not be
> > part of the void * struct, but of the executor's struct. So the
> > execQual code can switch to the memory context, and destroy it
> > appropriately.
> >
> > Second, we should make gram.y set a new "function type" value in the
> > TableExpr it creates, so that the downstream code (transformTableExpr,
> > ExecInitExpr, ruleutils.c) really knows that the given function is
> > XmlTableExpr, instead of guessing just because it's the only implemented
> > case. Probably this "function type" is an enum (currently with a single
> > value TableExprTypeXml or something like that) in primnodes.
>
> It has sense - I was not sure about it - because currently it is only one
> value, you mentioned it.

True. This is a minor point.

Are you able to do the memory context change I describe?

--
Álvaro Herrera https://www.2ndQuadrant.com/
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