database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-07-02 09:02:37 +03:00
Code Activity

Rearrange CustomScan API.

Browse Source 
Make it work more like FDW plans do: instead of assuming that there are
expressions in a CustomScan plan node that the core code doesn't know
about, insist that all subexpressions that need planner attention be in
a "custom_exprs" list in the Plan representation.  (Of course, the
custom plugin can break the list apart again at executor initialization.)
This lets us revert the parts of the patch that exposed setrefs.c and
subselect.c processing to the outside world.

Also revert the GetSpecialCustomVar stuff in ruleutils.c; that concept
may work in future, but it's far from fully baked right now.
This commit is contained in:
Tom Lane
2014-11-21 18:21:46 -05:00
parent c2ea2285e9
commit 447770404c
11 changed files with 109 additions and 164 deletions
Download Patch File Download Diff File Expand all files Collapse all files

70
src/backend/utils/adt/ruleutils.c
View File

@ -5493,26 +5493,6 @@ get_utility_query_def(Query *query, deparse_context *context)
}
}
/*
* GetSpecialCustomVar
*
* If a custom-scan provider uses a special varnode, this function will be
* called when deparsing; it should return an Expr node to be reversed-listed
* in lieu of the special Var.
*/
static Node *
GetSpecialCustomVar(CustomScanState *css, Var *varnode, PlanState **child_ps)
{
Assert(IsA(css, CustomScanState));
Assert(IS_SPECIAL_VARNO(varnode->varno));
if (!css->methods->GetSpecialCustomVar)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("%s does not support special varno reference",
css->methods->CustomName)));
return (Node *) css->methods->GetSpecialCustomVar(css, varnode, child_ps);
}
/*
* Display a Var appropriately.
@ -5542,8 +5522,6 @@ get_variable(Var *var, int levelsup, bool istoplevel, deparse_context *context)
int netlevelsup;
deparse_namespace *dpns;
deparse_columns *colinfo;
PlanState *child_ps = NULL;
Node *expr;
char *refname;
char *attname;
@ -5568,29 +5546,6 @@ get_variable(Var *var, int levelsup, bool istoplevel, deparse_context *context)
colinfo = deparse_columns_fetch(var->varno, dpns);
attnum = var->varattno;
}
else if (IS_SPECIAL_VARNO(var->varno) &&
IsA(dpns->planstate, CustomScanState) &&
(expr = GetSpecialCustomVar((CustomScanState *) dpns->planstate,
var, &child_ps)) != NULL)
{
deparse_namespace save_dpns;
if (child_ps)
push_child_plan(dpns, child_ps, &save_dpns);
/*
* Force parentheses because our caller probably assumed a Var is a
* simple expression.
*/
if (!IsA(expr, Var))
appendStringInfoChar(buf, '(');
get_rule_expr((Node *) expr, context, true);
if (!IsA(expr, Var))
appendStringInfoChar(buf, ')');
if (child_ps)
pop_child_plan(dpns, &save_dpns);
return NULL;
}
else if (var->varno == OUTER_VAR && dpns->outer_tlist)
{
TargetEntry *tle;
@ -5805,7 +5760,6 @@ get_name_for_var_field(Var *var, int fieldno,
AttrNumber attnum;
int netlevelsup;
deparse_namespace *dpns;
PlanState *child_ps = NULL;
TupleDesc tupleDesc;
Node *expr;
@ -5880,30 +5834,6 @@ get_name_for_var_field(Var *var, int fieldno,
rte = rt_fetch(var->varno, dpns->rtable);
attnum = var->varattno;
}
else if (IS_SPECIAL_VARNO(var->varno) &&
IsA(dpns->planstate, CustomScanState) &&
(expr = GetSpecialCustomVar((CustomScanState *) dpns->planstate,
var, &child_ps)) != NULL)
{
StringInfo saved = context->buf;
StringInfoData temp;
deparse_namespace save_dpns;
initStringInfo(&temp);
context->buf = &temp;
if (child_ps)
push_child_plan(dpns, child_ps, &save_dpns);
if (!IsA(expr, Var))
appendStringInfoChar(context->buf, '(');
get_rule_expr((Node *) expr, context, true);
if (!IsA(expr, Var))
appendStringInfoChar(context->buf, ')');
if (child_ps)
pop_child_plan(dpns, &save_dpns);
context->buf = saved;
return temp.data;
}
else if (var->varno == OUTER_VAR && dpns->outer_tlist)
{
TargetEntry *tle;