Modernize some code a bit

Modernize code in ExecRelCheck() and ExecConstraints() a bit,
preparing the way for some new code.

Co-authored-by: jian he <[email protected]>
Reviewed-by: Xuneng Zhou <[email protected]>
Reviewed-by: Navneet Kumar <[email protected]>
Reviewed-by: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/CACJufxHArQysbDkWFmvK+D1TPHQWWTxWN15cMuUaTYX3xhQXgg@mail.gmail.com

diff --git a/src/backend/executor/execMain.c b/src/backend/executor/execMain.c
index 1cd4dbd2b90d6d79bb39ad9f77ddb39eba519778..a22712755713087a8a519e0a4786e4d3753b3d7c 100644 (file)
--- a/src/backend/executor/execMain.c
+++ b/src/backend/executor/execMain.c
@@ -1855,7 +1855,6 @@ ExecRelCheck(ResultRelInfo *resultRelInfo,
    ConstrCheck *check = rel->rd_att->constr->check;
    ExprContext *econtext;
    MemoryContext oldContext;
-   int         i;
 
    /*
     * CheckConstraintFetch let this pass with only a warning, but now we
@@ -1874,9 +1873,8 @@ ExecRelCheck(ResultRelInfo *resultRelInfo,
    if (resultRelInfo->ri_CheckConstraintExprs == NULL)
    {
        oldContext = MemoryContextSwitchTo(estate->es_query_cxt);
-       resultRelInfo->ri_CheckConstraintExprs =
-           (ExprState **) palloc0(ncheck * sizeof(ExprState *));
-       for (i = 0; i < ncheck; i++)
+       resultRelInfo->ri_CheckConstraintExprs = palloc0_array(ExprState *, ncheck);
+       for (int i = 0; i < ncheck; i++)
        {
            Expr       *checkconstr;
 
@@ -1902,7 +1900,7 @@ ExecRelCheck(ResultRelInfo *resultRelInfo,
    econtext->ecxt_scantuple = slot;
 
    /* And evaluate the constraints */
-   for (i = 0; i < ncheck; i++)
+   for (int i = 0; i < ncheck; i++)
    {
        ExprState  *checkconstr = resultRelInfo->ri_CheckConstraintExprs[i];
 
@@ -2061,16 +2059,16 @@ ExecConstraints(ResultRelInfo *resultRelInfo,
 
    Assert(constr);             /* we should not be called otherwise */
 
+   /*
+    * Verify not-null constraints.
+    */
    if (constr->has_not_null)
    {
-       int         natts = tupdesc->natts;
-       int         attrChk;
-
-       for (attrChk = 1; attrChk <= natts; attrChk++)
+       for (AttrNumber attnum = 1; attnum <= tupdesc->natts; attnum++)
        {
-           Form_pg_attribute att = TupleDescAttr(tupdesc, attrChk - 1);
+           Form_pg_attribute att = TupleDescAttr(tupdesc, attnum - 1);
 
-           if (att->attnotnull && slot_attisnull(slot, attrChk))
+           if (att->attnotnull && slot_attisnull(slot, attnum))
            {
                char       *val_desc;
                Relation    orig_rel = rel;
@@ -2115,16 +2113,19 @@ ExecConstraints(ResultRelInfo *resultRelInfo,
                                                         64);
 
                ereport(ERROR,
-                       (errcode(ERRCODE_NOT_NULL_VIOLATION),
-                        errmsg("null value in column \"%s\" of relation \"%s\" violates not-null constraint",
-                               NameStr(att->attname),
-                               RelationGetRelationName(orig_rel)),
-                        val_desc ? errdetail("Failing row contains %s.", val_desc) : 0,
-                        errtablecol(orig_rel, attrChk)));
+                       errcode(ERRCODE_NOT_NULL_VIOLATION),
+                       errmsg("null value in column \"%s\" of relation \"%s\" violates not-null constraint",
+                              NameStr(att->attname),
+                              RelationGetRelationName(orig_rel)),
+                       val_desc ? errdetail("Failing row contains %s.", val_desc) : 0,
+                       errtablecol(orig_rel, attnum));
            }
        }
    }
 
+   /*
+    * Verify check constraints.
+    */
    if (rel->rd_rel->relchecks > 0)
    {
        const char *failed;