Movatterモバイル変換

[0]ホーム
URL:

Skip to content

Navigation Menu

Sign in
Appearance settings

Search code, repositories, users, issues, pull requests...

Provide feedback

We read every piece of feedback, and take your input very seriously.

Saved searches

Use saved searches to filter your results more quickly

 Sign up
Appearance settings

Commitebf76f2

Browse files
committed
Add TupleDescGetDefault()
This unifies some repetitive code.Note: I didn't push the "not found" error message into the newfunction, even though all existing callers would be able to make useof it. Using the existing error handling as-is would probably requireexposing the Relation type via tupdesc.h, which doesn't seemdesirable. (Or even if we changed it to just report the OID, it wouldinject the concept of a relation containing the tuple descriptor intotupdesc.h, which might be a layering violation. Perhaps some furtherimprovements could be considered here separately.)Discussion:https://www.postgresql.org/message-id/flat/52a125e4-ff9a-95f5-9f61-b87cf447e4da%40eisentraut.org
1 parent9dce220 commitebf76f2

File tree

5 files changed

+32
-41
lines changed

5 files changed

+32
-41
lines changed

‎src/backend/access/common/tupdesc.c

Lines changed: 25 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -927,3 +927,28 @@ BuildDescFromLists(const List *names, const List *types, const List *typmods, co
927927

928928
returndesc;
929929
}
930+
931+
/*
932+
* Get default expression (or NULL if none) for the given attribute number.
933+
*/
934+
Node*
935+
TupleDescGetDefault(TupleDesctupdesc,AttrNumberattnum)
936+
{
937+
Node*result=NULL;
938+
939+
if (tupdesc->constr)
940+
{
941+
AttrDefault*attrdef=tupdesc->constr->defval;
942+
943+
for (inti=0;i<tupdesc->constr->num_defval;i++)
944+
{
945+
if (attrdef[i].adnum==attnum)
946+
{
947+
result=stringToNode(attrdef[i].adbin);
948+
break;
949+
}
950+
}
951+
}
952+
953+
returnresult;
954+
}

‎src/backend/commands/tablecmds.c

Lines changed: 2 additions & 15 deletions
Original file line numberDiff line numberDiff line change
@@ -2795,22 +2795,9 @@ MergeAttributes(List *columns, const List *supers, char relpersistence,
27952795
*/
27962796
if (attribute->atthasdef)
27972797
{
2798-
Node *this_default = NULL;
2798+
Node *this_default;
27992799

2800-
/* Find default in constraint structure */
2801-
if (constr != NULL)
2802-
{
2803-
AttrDefault *attrdef = constr->defval;
2804-
2805-
for (int i = 0; i < constr->num_defval; i++)
2806-
{
2807-
if (attrdef[i].adnum == parent_attno)
2808-
{
2809-
this_default = stringToNode(attrdef[i].adbin);
2810-
break;
2811-
}
2812-
}
2813-
}
2800+
this_default = TupleDescGetDefault(tupleDesc, parent_attno);
28142801
if (this_default == NULL)
28152802
elog(ERROR, "default expression not found for attribute %d of relation \"%s\"",
28162803
parent_attno, RelationGetRelationName(relation));

‎src/backend/parser/parse_utilcmd.c

Lines changed: 2 additions & 11 deletions
Original file line numberDiff line numberDiff line change
@@ -1358,20 +1358,11 @@ expandTableLikeClause(RangeVar *heapRel, TableLikeClause *table_like_clause)
13581358
(table_like_clause->options&CREATE_TABLE_LIKE_GENERATED) :
13591359
(table_like_clause->options&CREATE_TABLE_LIKE_DEFAULTS)))
13601360
{
1361-
Node*this_default=NULL;
1362-
AttrDefault*attrdef=constr->defval;
1361+
Node*this_default;
13631362
AlterTableCmd*atsubcmd;
13641363
boolfound_whole_row;
13651364

1366-
/* Find default in constraint structure */
1367-
for (inti=0;i<constr->num_defval;i++)
1368-
{
1369-
if (attrdef[i].adnum==parent_attno)
1370-
{
1371-
this_default=stringToNode(attrdef[i].adbin);
1372-
break;
1373-
}
1374-
}
1365+
this_default=TupleDescGetDefault(tupleDesc,parent_attno);
13751366
if (this_default==NULL)
13761367
elog(ERROR,"default expression not found for attribute %d of relation \"%s\"",
13771368
parent_attno,RelationGetRelationName(relation));

‎src/backend/rewrite/rewriteHandler.c

Lines changed: 1 addition & 15 deletions
Original file line numberDiff line numberDiff line change
@@ -1246,21 +1246,7 @@ build_column_default(Relation rel, int attrno)
12461246
*/
12471247
if (att_tup->atthasdef)
12481248
{
1249-
if (rd_att->constr&&rd_att->constr->num_defval>0)
1250-
{
1251-
AttrDefault*defval=rd_att->constr->defval;
1252-
intndef=rd_att->constr->num_defval;
1253-
1254-
while (--ndef >=0)
1255-
{
1256-
if (attrno==defval[ndef].adnum)
1257-
{
1258-
/* Found it, convert string representation to node tree. */
1259-
expr=stringToNode(defval[ndef].adbin);
1260-
break;
1261-
}
1262-
}
1263-
}
1249+
expr=TupleDescGetDefault(rd_att,attrno);
12641250
if (expr==NULL)
12651251
elog(ERROR,"default expression not found for attribute %d of relation \"%s\"",
12661252
attrno,RelationGetRelationName(rel));

‎src/include/access/tupdesc.h

Lines changed: 2 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -151,4 +151,6 @@ extern TupleDesc BuildDescForRelation(const List *columns);
151151

152152
externTupleDescBuildDescFromLists(constList*names,constList*types,constList*typmods,constList*collations);
153153

154+
externNode*TupleDescGetDefault(TupleDesctupdesc,AttrNumberattnum);
155+
154156
#endif/* TUPDESC_H */

0 commit comments

Comments
 (0)
[8]ページ先頭
©2009-2025 Movatter.jp