database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-06-13 07:41:39 +03:00
Code Activity

Re-implement LIMIT/OFFSET as a plan node type, instead of a hack in

Browse Source 
ExecutorRun.  This allows LIMIT to work in a view.  Also, LIMIT in a
cursor declaration will behave in a reasonable fashion, whereas before
it was overridden by the FETCH count.
This commit is contained in:
Tom Lane
2000-10-26 21:38:24 +00:00
parent c9476bafdb
commit 2f35b4efdb
26 changed files with 572 additions and 232 deletions
Download Patch File Download Diff File Expand all files Collapse all files

25
src/backend/commands/command.c
View File

@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/commands/Attic/command.c,v 1.107 2000/10/16 17:08:05 momjian Exp $
* $Header: /cvsroot/pgsql/src/backend/commands/Attic/command.c,v 1.108 2000/10/26 21:34:44 tgl Exp $
*
* NOTES
* The PerformAddAttribute() code, like most of the relation
@ -111,7 +111,6 @@ PerformPortalFetch(char *name,
int feature;
QueryDesc *queryDesc;
MemoryContext oldcontext;
Const limcount;
/* ----------------
* sanity checks
@ -123,20 +122,6 @@ PerformPortalFetch(char *name,
return;
}
/* ----------------
* Create a const node from the given count value
* ----------------
*/
memset(&limcount, 0, sizeof(limcount));
limcount.type = T_Const;
limcount.consttype = INT4OID;
limcount.constlen = sizeof(int4);
limcount.constvalue = Int32GetDatum(count);
limcount.constisnull = false;
limcount.constbyval = true;
limcount.constisset = false;
limcount.constiscast = false;
/* ----------------
* get the portal from the portal name
* ----------------
@ -156,8 +141,7 @@ PerformPortalFetch(char *name,
oldcontext = MemoryContextSwitchTo(PortalGetHeapMemory(portal));
/* ----------------
* setup "feature" to tell the executor what direction and
* how many tuples to fetch.
* setup "feature" to tell the executor which direction to go in.
* ----------------
*/
if (forward)
@ -166,7 +150,7 @@ PerformPortalFetch(char *name,
feature = EXEC_BACK;
/* ----------------
* tell the destination to prepare to recieve some tuples
* tell the destination to prepare to receive some tuples
* ----------------
*/
queryDesc = PortalGetQueryDesc(portal);
@ -194,8 +178,7 @@ PerformPortalFetch(char *name,
* execute the portal fetch operation
* ----------------
*/
ExecutorRun(queryDesc, PortalGetState(portal), feature,
(Node *) NULL, (Node *) &limcount);
ExecutorRun(queryDesc, PortalGetState(portal), feature, (long) count);
if (dest == None) /* MOVE */
pfree(queryDesc);