diff --git a/doc/src/sgml/ref/lock.sgml b/doc/src/sgml/ref/lock.sgml
index d576890acb96797078a8e1b18b7080435eb14b42..58e53371c94488d14598d9a1fa210764ff35cf66 100644
--- a/doc/src/sgml/ref/lock.sgml
+++ b/doc/src/sgml/ref/lock.sgml
@@ -1,5 +1,5 @@
@@ -15,7 +15,7 @@ Postgres documentation
LOCK
- Explicitly lock a table inside a transaction
+ Explicitly lock a table / tables inside a transaction
@@ -23,8 +23,8 @@ Postgres documentation
2001-07-09
-LOCK [ TABLE ] name
-LOCK [ TABLE ] name IN lockmode MODE
+LOCK [ TABLE ] name [,...]
+LOCK [ TABLE ] name [,...] IN lockmode MODE
where lockmode is one of:
@@ -373,6 +373,7 @@ ERROR name: Table does not exist.
An example for this rule was given previously when discussing the
use of SHARE ROW EXCLUSIVE mode rather than SHARE mode.
+
@@ -383,6 +384,12 @@ ERROR name: Table does not exist.
+
+ When locking multiple tables, the command LOCK a, b; is equivalent to LOCK
+ a; LOCK b;. The tables are locked one-by-one in the order specified in the
+ LOCK command.
+
+
1999-06-08
@@ -406,6 +413,7 @@ ERROR name: Table does not exist.
LOCK works only inside transactions.
+
diff --git a/src/backend/commands/command.c b/src/backend/commands/command.c
index 744129f726fd57f2c3e04fb92112a9b9e0a98543..827608363cb314c5fd38e6565fdd97876f32da25 100644
--- a/src/backend/commands/command.c
+++ b/src/backend/commands/command.c
@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/commands/Attic/command.c,v 1.136 2001/07/16 05:06:57 tgl Exp $
+ * $Header: /cvsroot/pgsql/src/backend/commands/Attic/command.c,v 1.137 2001/08/04 19:38:59 momjian Exp $
*
* NOTES
* The PerformAddAttribute() code, like most of the relation
@@ -1984,8 +1984,7 @@ needs_toast_table(Relation rel)
MAXALIGN(data_length);
return (tuple_length > TOAST_TUPLE_THRESHOLD);
}
-
-
+
/*
*
* LOCK TABLE
@@ -1994,26 +1993,104 @@ needs_toast_table(Relation rel)
void
LockTableCommand(LockStmt *lockstmt)
{
- Relation rel;
- int aclresult;
+ int relCnt;
- rel = heap_openr(lockstmt->relname, NoLock);
+ relCnt = length(lockstmt -> rellist);
- if (rel->rd_rel->relkind != RELKIND_RELATION)
- elog(ERROR, "LOCK TABLE: %s is not a table", lockstmt->relname);
+ /* Handle a single relation lock specially to avoid overhead on likely the
+ most common case */
- if (lockstmt->mode == AccessShareLock)
- aclresult = pg_aclcheck(lockstmt->relname, GetUserId(), ACL_SELECT);
- else
- aclresult = pg_aclcheck(lockstmt->relname, GetUserId(),
- ACL_UPDATE | ACL_DELETE);
+ if(relCnt == 1)
+ {
+
+ /* Locking a single table */
+
+ Relation rel;
+ int aclresult;
+ char *relname;
+
+ relname = strVal(lfirst(lockstmt->rellist));
+
+ freeList(lockstmt->rellist);
+
+ rel = heap_openr(relname, NoLock);
+
+ if (rel->rd_rel->relkind != RELKIND_RELATION)
+ elog(ERROR, "LOCK TABLE: %s is not a table", relname);
+
+ if (lockstmt->mode == AccessShareLock)
+ aclresult = pg_aclcheck(relname, GetUserId(),
+ ACL_SELECT);
+ else
+ aclresult = pg_aclcheck(relname, GetUserId(),
+ ACL_UPDATE | ACL_DELETE);
+
+ if (aclresult != ACLCHECK_OK)
+ elog(ERROR, "LOCK TABLE: permission denied");
+
+ LockRelation(rel, lockstmt->mode);
+
+ pfree(relname);
+
+ heap_close(rel, NoLock); /* close rel, keep lock */
+ }
+ else
+ {
+ List *p;
+ Relation *RelationArray;
+ Relation *pRel;
- if (aclresult != ACLCHECK_OK)
- elog(ERROR, "LOCK TABLE: permission denied");
+ /* Locking multiple tables */
- LockRelation(rel, lockstmt->mode);
+ /* Create an array of relations */
- heap_close(rel, NoLock); /* close rel, keep lock */
+ RelationArray = palloc(relCnt * sizeof(Relation));
+ pRel = RelationArray;
+
+ /* Iterate over the list and populate the relation array */
+
+ foreach(p, lockstmt->rellist)
+ {
+ char* relname = strVal(lfirst(p));
+ int aclresult;
+
+ *pRel = heap_openr(relname, NoLock);
+
+ if ((*pRel)->rd_rel->relkind != RELKIND_RELATION)
+ elog(ERROR, "LOCK TABLE: %s is not a table",
+ relname);
+
+ if (lockstmt->mode == AccessShareLock)
+ aclresult = pg_aclcheck(relname, GetUserId(),
+ ACL_SELECT);
+ else
+ aclresult = pg_aclcheck(relname, GetUserId(),
+ ACL_UPDATE | ACL_DELETE);
+
+ if (aclresult != ACLCHECK_OK)
+ elog(ERROR, "LOCK TABLE: permission denied");
+
+ pRel++;
+ pfree(relname);
+ }
+
+ /* Now, lock all the relations, closing each after it is locked
+ (Keeping the locks)
+ */
+
+ for(pRel = RelationArray;
+ pRel < RelationArray + relCnt;
+ pRel++)
+ {
+ LockRelation(*pRel, lockstmt->mode);
+
+ heap_close(*pRel, NoLock);
+ }
+
+ /* Free the relation array */
+
+ pfree(RelationArray);
+ }
}
diff --git a/src/backend/nodes/copyfuncs.c b/src/backend/nodes/copyfuncs.c
index 2ea063f336fccb7a7e125e43721e0c1c2a8b7983..65bd5f27e9e1c487a21c4c32ace2820c6b02eb18 100644
--- a/src/backend/nodes/copyfuncs.c
+++ b/src/backend/nodes/copyfuncs.c
@@ -15,7 +15,7 @@
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/nodes/copyfuncs.c,v 1.148 2001/07/16 19:07:37 momjian Exp $
+ * $Header: /cvsroot/pgsql/src/backend/nodes/copyfuncs.c,v 1.149 2001/08/04 19:38:59 momjian Exp $
*
*-------------------------------------------------------------------------
*/
@@ -2425,8 +2425,8 @@ _copyLockStmt(LockStmt *from)
{
LockStmt *newnode = makeNode(LockStmt);
- if (from->relname)
- newnode->relname = pstrdup(from->relname);
+ Node_Copy(from, newnode, rellist);
+
newnode->mode = from->mode;
return newnode;
diff --git a/src/backend/nodes/equalfuncs.c b/src/backend/nodes/equalfuncs.c
index eb194f667f49769137915d64fc7f788ab39740c9..3a9629cde381ee617c4a838ef456d7702e4622c6 100644
--- a/src/backend/nodes/equalfuncs.c
+++ b/src/backend/nodes/equalfuncs.c
@@ -20,7 +20,7 @@
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/nodes/equalfuncs.c,v 1.96 2001/07/16 19:07:38 momjian Exp $
+ * $Header: /cvsroot/pgsql/src/backend/nodes/equalfuncs.c,v 1.97 2001/08/04 19:38:59 momjian Exp $
*
*-------------------------------------------------------------------------
*/
@@ -1283,7 +1283,7 @@ _equalDropUserStmt(DropUserStmt *a, DropUserStmt *b)
static bool
_equalLockStmt(LockStmt *a, LockStmt *b)
{
- if (!equalstr(a->relname, b->relname))
+ if (!equal(a->rellist, b->rellist))
return false;
if (a->mode != b->mode)
return false;
diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index 00c66246ff96aea1c99bc47b3c38258c84328a46..130d259aaadf99a6444a8a9ee3ef2e4ffbad9277 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -11,7 +11,7 @@
*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/parser/gram.y,v 2.238 2001/07/16 19:07:40 momjian Exp $
+ * $Header: /cvsroot/pgsql/src/backend/parser/gram.y,v 2.239 2001/08/04 19:38:59 momjian Exp $
*
* HISTORY
* AUTHOR DATE MAJOR EVENT
@@ -3280,11 +3280,11 @@ DeleteStmt: DELETE FROM relation_expr where_clause
}
;
-LockStmt: LOCK_P opt_table relation_name opt_lock
+LockStmt: LOCK_P opt_table relation_name_list opt_lock
{
LockStmt *n = makeNode(LockStmt);
- n->relname = $3;
+ n->rellist = $3;
n->mode = $4;
$$ = (Node *)n;
}
diff --git a/src/include/nodes/parsenodes.h b/src/include/nodes/parsenodes.h
index 9fa703454f8c39df69abe85aba6d157effd1472d..ed379ab02e45a4f7a8b702a71617db095e934152 100644
--- a/src/include/nodes/parsenodes.h
+++ b/src/include/nodes/parsenodes.h
@@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $Id: parsenodes.h,v 1.136 2001/07/16 19:07:40 momjian Exp $
+ * $Id: parsenodes.h,v 1.137 2001/08/04 19:38:59 momjian Exp $
*
*-------------------------------------------------------------------------
*/
@@ -760,7 +760,7 @@ typedef struct VariableResetStmt
typedef struct LockStmt
{
NodeTag type;
- char *relname; /* relation to lock */
+ List *rellist; /* relations to lock */
int mode; /* lock mode */
} LockStmt;
diff --git a/src/interfaces/ecpg/preproc/preproc.y b/src/interfaces/ecpg/preproc/preproc.y
index 88330ad3c1de5a9d5af76a53b01ed43e8ca6f059..09180f85c9c28b38ae68378f4f0e392a08295277 100644
--- a/src/interfaces/ecpg/preproc/preproc.y
+++ b/src/interfaces/ecpg/preproc/preproc.y
@@ -2421,7 +2421,7 @@ DeleteStmt: DELETE FROM relation_expr where_clause
}
;
-LockStmt: LOCK_P opt_table relation_name opt_lock
+LockStmt: LOCK_P opt_table relation_name_list opt_lock
{
$$ = cat_str(4, make_str("lock"), $2, $3, $4);
}