Add SHARE UPDATE EXCLUSIVE lock mode, coming soon to a VACUUM near you.

Name chosen per pghackers discussion around 6/22/01.

diff --git a/doc/src/sgml/mvcc.sgml b/doc/src/sgml/mvcc.sgml
index 2eaf008..6d7013a 100644 (file)
--- a/doc/src/sgml/mvcc.sgml
+++ b/doc/src/sgml/mvcc.sgml
@@ -1,5 +1,5 @@
 <!--
-$Header: /cvsroot/pgsql/doc/src/sgml/mvcc.sgml,v 2.15 2001/05/17 21:50:16 petere Exp $
+$Header: /cvsroot/pgsql/doc/src/sgml/mvcc.sgml,v 2.16 2001/07/09 22:18:33 tgl Exp $
 -->
 
  <chapter id="mvcc">
@@ -443,6 +443,25 @@ ERROR:  Can't serialize access due to concurrent update
 
       <varlistentry>
        <term>
+       ShareUpdateExclusiveLock
+       </term>
+       <listitem>
+       <para>
+        Acquired by <command>VACUUM</command> (without <option>FULL</option>)
+        and <command>LOCK TABLE</command> table
+        for <option>IN SHARE UPDATE EXCLUSIVE MODE</option>
+        statements.
+       </para>
+
+       <para>
+        Conflicts with ShareUpdateExclusiveLock, ShareLock,
+        ShareRowExclusiveLock, ExclusiveLock and AccessExclusiveLock modes.
+       </para>
+       </listitem>
+      </varlistentry>
+
+      <varlistentry>
+       <term>
        ShareLock
        </term>
        <listitem>
@@ -454,7 +473,8 @@ ERROR:  Can't serialize access due to concurrent update
        </para>
 
        <para>
-        Conflicts with RowExclusiveLock, ShareRowExclusiveLock,
+        Conflicts with RowExclusiveLock, ShareUpdateExclusiveLock,
+        ShareRowExclusiveLock,
         ExclusiveLock and AccessExclusiveLock modes.
        </para>
        </listitem>
@@ -471,7 +491,8 @@ ERROR:  Can't serialize access due to concurrent update
        </para>
 
        <para>
-        Conflicts with RowExclusiveLock, ShareLock, ShareRowExclusiveLock,
+        Conflicts with RowExclusiveLock, ShareUpdateExclusiveLock,
+        ShareLock, ShareRowExclusiveLock,
         ExclusiveLock and AccessExclusiveLock modes.
        </para>
        </listitem>
@@ -488,7 +509,8 @@ ERROR:  Can't serialize access due to concurrent update
        </para>
 
        <para>
-        Conflicts with RowShareLock, RowExclusiveLock, ShareLock,
+        Conflicts with RowShareLock, RowExclusiveLock,
+        ShareUpdateExclusiveLock, ShareLock,
         ShareRowExclusiveLock, ExclusiveLock and AccessExclusiveLock
         modes.
        </para>
@@ -503,13 +525,13 @@ ERROR:  Can't serialize access due to concurrent update
        <para>
         Acquired by <command>ALTER TABLE</command>,
         <command>DROP TABLE</command>,
-        <command>VACUUM</command> and <command>LOCK TABLE</command>
+        <command>VACUUM FULL</command> and <command>LOCK TABLE</command>
         statements.
        </para>
 
        <para>
         Conflicts with all modes (AccessShareLock, RowShareLock,
-        RowExclusiveLock, ShareLock,
+        RowExclusiveLock, ShareUpdateExclusiveLock, ShareLock,
         ShareRowExclusiveLock, ExclusiveLock and AccessExclusiveLock).
        </para>
        </listitem>

diff --git a/doc/src/sgml/ref/lock.sgml b/doc/src/sgml/ref/lock.sgml
index bffbb7c..d576890 100644 (file)
--- a/doc/src/sgml/ref/lock.sgml
+++ b/doc/src/sgml/ref/lock.sgml
@@ -1,5 +1,5 @@
 <!--
-$Header: /cvsroot/pgsql/doc/src/sgml/ref/lock.sgml,v 1.23 2000/12/25 23:15:26 petere Exp $
+$Header: /cvsroot/pgsql/doc/src/sgml/ref/lock.sgml,v 1.24 2001/07/09 22:18:33 tgl Exp $
 Postgres documentation
 -->
 
@@ -20,12 +20,16 @@ Postgres documentation
  </refnamediv>
  <refsynopsisdiv>
   <refsynopsisdivinfo>
-   <date>1999-07-20</date>
+   <date>2001-07-09</date>
   </refsynopsisdivinfo>
   <synopsis>
 LOCK [ TABLE ] <replaceable class="PARAMETER">name</replaceable>
-LOCK [ TABLE ] <replaceable class="PARAMETER">name</replaceable> IN [ ROW | ACCESS ] { SHARE | EXCLUSIVE } MODE
-LOCK [ TABLE ] <replaceable class="PARAMETER">name</replaceable> IN SHARE ROW EXCLUSIVE MODE
+LOCK [ TABLE ] <replaceable class="PARAMETER">name</replaceable> IN <replaceable class="PARAMETER">lockmode</replaceable> MODE
+
+where <replaceable class="PARAMETER">lockmode</replaceable> is one of:
+
+       ACCESS SHARE | ROW SHARE | ROW EXCLUSIVE | SHARE UPDATE EXCLUSIVE |
+       SHARE | SHARE ROW EXCLUSIVE | EXCLUSIVE | ACCESS EXCLUSIVE
   </synopsis>
 
   <refsect2 id="R2-SQL-LOCK-1">
@@ -33,7 +37,6 @@ LOCK [ TABLE ] <replaceable class="PARAMETER">name</replaceable> IN SHARE ROW EX
     <date>1999-06-09</date>
    </refsect2info>
 
-
    <title>
     Inputs
    </title>
@@ -62,7 +65,7 @@ LOCK [ TABLE ] <replaceable class="PARAMETER">name</replaceable> IN SHARE ROW EX
        This is the least restrictive lock mode.  It conflicts only with
        ACCESS EXCLUSIVE mode. It is used to protect a table from being
        modified by concurrent <command>ALTER TABLE</command>, 
-       <command>DROP TABLE</command> and <command>VACUUM</command> 
+       <command>DROP TABLE</command> and <command>VACUUM FULL</command>
        commands.
        </para>
       </listitem>
@@ -103,6 +106,25 @@ LOCK [ TABLE ] <replaceable class="PARAMETER">name</replaceable> IN SHARE ROW EX
      </varlistentry>
 
      <varlistentry>
+      <term>SHARE UPDATE EXCLUSIVE MODE</term>
+      <listitem>
+       <note>
+       <para>
+        Automatically acquired by <command>VACUUM</command> (without
+        <option>FULL</option>).
+       </para>
+       </note>
+
+       <para>
+       Conflicts with SHARE UPDATE EXCLUSIVE, SHARE, SHARE ROW EXCLUSIVE,
+       EXCLUSIVE and
+       ACCESS EXCLUSIVE modes. This mode protects a table against
+       concurrent schema changes and VACUUMs.
+       </para>
+      </listitem>
+     </varlistentry>
+
+     <varlistentry>
       <term>SHARE MODE</term>
       <listitem>
        <note>
@@ -113,9 +135,10 @@ LOCK [ TABLE ] <replaceable class="PARAMETER">name</replaceable> IN SHARE ROW EX
        </note>
 
        <para>
-       Conflicts with ROW EXCLUSIVE, SHARE ROW EXCLUSIVE, EXCLUSIVE and
+       Conflicts with ROW EXCLUSIVE, SHARE UPDATE EXCLUSIVE,
+       SHARE ROW EXCLUSIVE, EXCLUSIVE and
        ACCESS EXCLUSIVE modes. This mode protects a table against
-       concurrent updates.
+       concurrent data updates.
        </para>
       </listitem>
      </varlistentry>
@@ -125,14 +148,14 @@ LOCK [ TABLE ] <replaceable class="PARAMETER">name</replaceable> IN SHARE ROW EX
       <listitem>
        <note>
        <para>
-       This is like EXCLUSIVE MODE, but allows SHARE ROW locks
+       This is like EXCLUSIVE MODE, but allows ROW SHARE locks
         by others.
        </para>
        </note>
 
        <para>
-        Conflicts with ROW EXCLUSIVE, SHARE, SHARE ROW EXCLUSIVE,
-       EXCLUSIVE and ACCESS EXCLUSIVE modes.
+        Conflicts with ROW EXCLUSIVE, SHARE UPDATE EXCLUSIVE, SHARE,
+       SHARE ROW EXCLUSIVE, EXCLUSIVE and ACCESS EXCLUSIVE modes.
        </para>
       </listitem>
      </varlistentry>
@@ -149,7 +172,8 @@ LOCK [ TABLE ] <replaceable class="PARAMETER">name</replaceable> IN SHARE ROW EX
        </note>
 
        <para>
-       Conflicts with ROW SHARE, ROW EXCLUSIVE, SHARE, SHARE ROW EXCLUSIVE,
+       Conflicts with ROW SHARE, ROW EXCLUSIVE, SHARE UPDATE EXCLUSIVE,
+       SHARE, SHARE ROW EXCLUSIVE,
        EXCLUSIVE and ACCESS EXCLUSIVE modes.
        </para>
       </listitem>
@@ -161,9 +185,10 @@ LOCK [ TABLE ] <replaceable class="PARAMETER">name</replaceable> IN SHARE ROW EX
        <note>
        <para>
         Automatically acquired by <command>ALTER TABLE</command>,
-        <command>DROP TABLE</command>, <command>VACUUM</command> statements.
-        This is the most restrictive lock mode which conflicts with all other
-        lock modes and protects a locked table from any concurrent operations.
+        <command>DROP TABLE</command>, <command>VACUUM FULL</command>
+        statements.
+        This is the most restrictive lock mode which
+        protects a locked table from any concurrent operations.
        </para>
        </note>
 
@@ -174,6 +199,10 @@ LOCK [ TABLE ] <replaceable class="PARAMETER">name</replaceable> IN SHARE ROW EX
         lock mode option).
        </para>
        </note>
+
+       <para>
+       Conflicts with all lock modes.
+       </para>
       </listitem>
      </varlistentry>
     </variablelist>
@@ -241,7 +270,11 @@ ERROR <replaceable class="PARAMETER">name</replaceable>: Table does not exist.
      <term>EXCLUSIVE</term>
      <listitem>
       <para>
-       Exclusive lock that prevents other locks from being granted.
+       An exclusive lock prevents other locks of the same type from being
+       granted.  (Note: ROW EXCLUSIVE mode does not follow this naming
+       convention perfectly, since it is shared at the level of the table;
+       it is exclusive only with respect to specific rows that are being
+       updated.)
       </para>
      </listitem>
     </varlistentry>
@@ -250,7 +283,8 @@ ERROR <replaceable class="PARAMETER">name</replaceable>: Table does not exist.
      <term>SHARE</term>
      <listitem>
       <para>
-       Allows others to share lock.  Prevents EXCLUSIVE locks.
+      A shared lock allows others to also hold the same type of lock,
+      but prevents the corresponding EXCLUSIVE lock from being granted.
       </para>
      </listitem>
     </varlistentry>
@@ -273,13 +307,6 @@ ERROR <replaceable class="PARAMETER">name</replaceable>: Table does not exist.
      </listitem>
     </varlistentry>
    </variablelist>
-
-   <note>
-    <para>
-     If EXCLUSIVE or SHARE are not specified, EXCLUSIVE is assumed.
-     Locks exist for the duration of the transaction.
-    </para>
-   </note>
   </para>
 
   <para>
@@ -370,8 +397,8 @@ ERROR <replaceable class="PARAMETER">name</replaceable>: Table does not exist.
    </para>
 
    <para>
-    Except for ACCESS SHARE/EXCLUSIVE lock modes, all other
-    <productname>Postgres</productname> lock modes and the
+    Except for ACCESS SHARE, ACCESS EXCLUSIVE, and SHARE UPDATE EXCLUSIVE lock
+    modes, the <productname>Postgres</productname> lock modes and the
     <command>LOCK TABLE</command> syntax are compatible with those
     present in <productname>Oracle</productname>.
    </para>

diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index cf518f3..7e6f782 100644 (file)
--- 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 2.233 2001/06/30 22:03:25 petere Exp $
+ *       $Header: /cvsroot/pgsql/src/backend/parser/gram.y,v 2.234 2001/07/09 22:18:33 tgl Exp $
  *
  * HISTORY
  *       AUTHOR                        DATE                    MAJOR EVENT
@@ -153,7 +153,7 @@ static void doNegateFloat(Value *v);
 %type <list>   createdb_opt_list, createdb_opt_item
 
 %type <ival>   opt_lock, lock_type
-%type <boolean>        opt_lmode, opt_force
+%type <boolean>        opt_force
 
 %type <ival>    user_createdb_clause, user_createuser_clause
 %type <str>            user_passwd_clause
@@ -3277,18 +3277,18 @@ LockStmt:       LOCK_P opt_table relation_name opt_lock
                                }
                ;
 
-opt_lock:  IN lock_type MODE           { $$ = $2; }
+opt_lock:  IN lock_type MODE   { $$ = $2; }
                | /*EMPTY*/                             { $$ = AccessExclusiveLock; }
                ;
 
-lock_type:  SHARE ROW EXCLUSIVE        { $$ = ShareRowExclusiveLock; }
-               | ROW opt_lmode                 { $$ = ($2? RowShareLock: RowExclusiveLock); }
-               | ACCESS opt_lmode              { $$ = ($2? AccessShareLock: AccessExclusiveLock); }
-               | opt_lmode                             { $$ = ($1? ShareLock: ExclusiveLock); }
-               ;
-
-opt_lmode:     SHARE                           { $$ = TRUE; }
-               | EXCLUSIVE                             { $$ = FALSE; }
+lock_type:  ACCESS SHARE               { $$ = AccessShareLock; }
+               | ROW SHARE                             { $$ = RowShareLock; }
+               | ROW EXCLUSIVE                 { $$ = RowExclusiveLock; }
+               | SHARE UPDATE EXCLUSIVE { $$ = ShareUpdateExclusiveLock; }
+               | SHARE                                 { $$ = ShareLock; }
+               | SHARE ROW EXCLUSIVE   { $$ = ShareRowExclusiveLock; }
+               | EXCLUSIVE                             { $$ = ExclusiveLock; }
+               | ACCESS EXCLUSIVE              { $$ = AccessExclusiveLock; }
                ;
 
 

diff --git a/src/backend/storage/lmgr/lmgr.c b/src/backend/storage/lmgr/lmgr.c
index fa3812a..1086134 100644 (file)
--- a/src/backend/storage/lmgr/lmgr.c
+++ b/src/backend/storage/lmgr/lmgr.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *       $Header: /cvsroot/pgsql/src/backend/storage/lmgr/lmgr.c,v 1.48 2001/06/22 00:04:59 tgl Exp $
+ *       $Header: /cvsroot/pgsql/src/backend/storage/lmgr/lmgr.c,v 1.49 2001/07/09 22:18:33 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -33,25 +33,35 @@ static LOCKMASK LockConflicts[] = {
        (1 << ExclusiveLock) | (1 << AccessExclusiveLock),
 
        /* RowExclusiveLock */
-       (1 << ExclusiveLock) | (1 << ShareRowExclusiveLock) | (1 << ShareLock) |
-       (1 << AccessExclusiveLock),
+       (1 << ShareLock) | (1 << ShareRowExclusiveLock) |
+       (1 << ExclusiveLock) | (1 << AccessExclusiveLock),
+
+       /* ShareUpdateExclusiveLock */
+       (1 << ShareUpdateExclusiveLock) |
+       (1 << ShareLock) | (1 << ShareRowExclusiveLock) |
+       (1 << ExclusiveLock) | (1 << AccessExclusiveLock),
 
        /* ShareLock */
-       (1 << ExclusiveLock) | (1 << ShareRowExclusiveLock) |
-       (1 << RowExclusiveLock) | (1 << AccessExclusiveLock),
+       (1 << RowExclusiveLock) | (1 << ShareUpdateExclusiveLock) |
+       (1 << ShareRowExclusiveLock) |
+       (1 << ExclusiveLock) | (1 << AccessExclusiveLock),
 
        /* ShareRowExclusiveLock */
-       (1 << ExclusiveLock) | (1 << ShareRowExclusiveLock) |
-       (1 << ShareLock) | (1 << RowExclusiveLock) | (1 << AccessExclusiveLock),
+       (1 << RowExclusiveLock) | (1 << ShareUpdateExclusiveLock) |
+       (1 << ShareLock) | (1 << ShareRowExclusiveLock) |
+       (1 << ExclusiveLock) | (1 << AccessExclusiveLock),
 
        /* ExclusiveLock */
-       (1 << ExclusiveLock) | (1 << ShareRowExclusiveLock) | (1 << ShareLock) |
-       (1 << RowExclusiveLock) | (1 << RowShareLock) | (1 << AccessExclusiveLock),
+       (1 << RowShareLock) |
+       (1 << RowExclusiveLock) | (1 << ShareUpdateExclusiveLock) |
+       (1 << ShareLock) | (1 << ShareRowExclusiveLock) |
+       (1 << ExclusiveLock) | (1 << AccessExclusiveLock),
 
        /* AccessExclusiveLock */
-       (1 << ExclusiveLock) | (1 << ShareRowExclusiveLock) | (1 << ShareLock) |
-       (1 << RowExclusiveLock) | (1 << RowShareLock) |
-       (1 << AccessExclusiveLock) | (1 << AccessShareLock)
+       (1 << AccessShareLock) | (1 << RowShareLock) |
+       (1 << RowExclusiveLock) | (1 << ShareUpdateExclusiveLock) |
+       (1 << ShareLock) | (1 << ShareRowExclusiveLock) |
+       (1 << ExclusiveLock) | (1 << AccessExclusiveLock)
 
 };
 
@@ -63,14 +73,16 @@ static int  LockPrios[] = {
        2,
        /* RowExclusiveLock */
        3,
-       /* ShareLock */
+       /* ShareUpdateExclusiveLock */
        4,
-       /* ShareRowExclusiveLock */
+       /* ShareLock */
        5,
-       /* ExclusiveLock */
+       /* ShareRowExclusiveLock */
        6,
+       /* ExclusiveLock */
+       7,
        /* AccessExclusiveLock */
-       7
+       8
 };
 
 LOCKMETHOD     LockTableId = (LOCKMETHOD) NULL;

diff --git a/src/backend/storage/lmgr/lock.c b/src/backend/storage/lmgr/lock.c
index 3eb0104..cff407a 100644 (file)
--- a/src/backend/storage/lmgr/lock.c
+++ b/src/backend/storage/lmgr/lock.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *       $Header: /cvsroot/pgsql/src/backend/storage/lmgr/lock.c,v 1.90 2001/06/27 23:31:39 tgl Exp $
+ *       $Header: /cvsroot/pgsql/src/backend/storage/lmgr/lock.c,v 1.91 2001/07/09 22:18:33 tgl Exp $
  *
  * NOTES
  *       Outside modules can create a lock table and acquire/release
@@ -58,6 +58,7 @@ static char *lock_mode_names[] =
        "AccessShareLock",
        "RowShareLock",
        "RowExclusiveLock",
+       "ShareUpdateExclusiveLock",
        "ShareLock",
        "ShareRowExclusiveLock",
        "ExclusiveLock",

diff --git a/src/include/storage/lmgr.h b/src/include/storage/lmgr.h
index c279ef6..1fb490e 100644 (file)
--- a/src/include/storage/lmgr.h
+++ b/src/include/storage/lmgr.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: lmgr.h,v 1.31 2001/06/22 00:04:59 tgl Exp $
+ * $Id: lmgr.h,v 1.32 2001/07/09 22:18:34 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -25,13 +25,14 @@
 #define AccessShareLock                        1               /* SELECT */
 #define RowShareLock                   2               /* SELECT FOR UPDATE */
 #define RowExclusiveLock               3               /* INSERT, UPDATE, DELETE */
-#define ShareLock                              4               /* CREATE INDEX */
-#define ShareRowExclusiveLock  5               /* like EXCLUSIVE MODE, allows
-                                                                                * SHARE ROW */
-#define ExclusiveLock                  6               /* blocks ROW SHARE/SELECT...FOR
+#define ShareUpdateExclusiveLock 4             /* VACUUM (non-FULL) */
+#define ShareLock                              5               /* CREATE INDEX */
+#define ShareRowExclusiveLock  6               /* like EXCLUSIVE MODE, but allows
+                                                                                * ROW SHARE */
+#define ExclusiveLock                  7               /* blocks ROW SHARE/SELECT...FOR
                                                                                 * UPDATE */
-#define AccessExclusiveLock            7               /* ALTER TABLE, DROP TABLE,
-                                                                                * VACUUM, and unqualified LOCK
+#define AccessExclusiveLock            8               /* ALTER TABLE, DROP TABLE,
+                                                                                * VACUUM FULL, and unqualified LOCK
                                                                                 * TABLE */
 
 /*

diff --git a/src/include/storage/lock.h b/src/include/storage/lock.h
index 30a1364..1010e67 100644 (file)
--- a/src/include/storage/lock.h
+++ b/src/include/storage/lock.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: lock.h,v 1.50 2001/06/27 23:31:39 tgl Exp $
+ * $Id: lock.h,v 1.51 2001/07/09 22:18:34 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -49,7 +49,7 @@ typedef int LOCKMODE;
 typedef int LOCKMETHOD;
 
 /* MAX_LOCKMODES cannot be larger than the # of bits in LOCKMASK */
-#define MAX_LOCKMODES          8
+#define MAX_LOCKMODES          10
 
 /*
  * MAX_LOCK_METHODS corresponds to the number of spin locks allocated in
@@ -91,7 +91,7 @@ typedef int LOCKMETHOD;
  *
  * prio -- each lockmode has a priority, so, for example, waiting
  *             writers can be given priority over readers (to avoid
- *             starvation).
+ *             starvation).  XXX this field is not actually used at present!
  *
  * masterlock -- synchronizes access to the table
  */

diff --git a/src/interfaces/ecpg/preproc/preproc.y b/src/interfaces/ecpg/preproc/preproc.y
index 2228c12..e062602 100644 (file)
--- a/src/interfaces/ecpg/preproc/preproc.y
+++ b/src/interfaces/ecpg/preproc/preproc.y
@@ -326,7 +326,7 @@ make_name(void)
 %type  <str>   createdb_opt_list opt_encoding OptInherit Geometric
 %type  <str>    DropdbStmt ClusterStmt grantee RevokeStmt Bit bit
 %type  <str>   GrantStmt privileges operation_commalist operation PosAllConst
-%type  <str>   opt_cursor opt_lmode ConstraintsSetStmt comment_tg AllConst
+%type  <str>   opt_cursor ConstraintsSetStmt comment_tg AllConst
 %type  <str>   case_expr when_clause_list case_default case_arg when_clause
 %type  <str>    select_clause opt_select_limit select_limit_value ConstraintTimeSpec
 %type  <str>    select_offset_value ReindexStmt join_type opt_boolean
@@ -2440,15 +2440,15 @@ opt_lock:  IN lock_type MODE            { $$ = cat_str(3, make_str("in"), $2, ma
                 | /*EMPTY*/             { $$ = EMPTY;}
                 ;
 
-lock_type:  SHARE ROW EXCLUSIVE        { $$ = make_str("share row exclusive"); }
-                | ROW opt_lmode         { $$ = cat2_str(make_str("row"), $2);}
-                | ACCESS opt_lmode      { $$ = cat2_str(make_str("access"), $2);}
-                | opt_lmode             { $$ = $1; }
-                ;
-
-opt_lmode:      SHARE                           { $$ = make_str("share"); }
-                | EXCLUSIVE                     { $$ = make_str("exclusive"); }
-                ;
+lock_type:  ACCESS SHARE               { $$ = make_str("access share"); }
+               | ROW SHARE                             { $$ = make_str("access share"); }
+               | ROW EXCLUSIVE                 { $$ = make_str("row exclusive"); }
+               | SHARE UPDATE EXCLUSIVE { $$ = make_str("share update exclusive"); }
+               | SHARE                                 { $$ = make_str("share"); }
+               | SHARE ROW EXCLUSIVE   { $$ = make_str("share row exclusive"); }
+               | EXCLUSIVE                             { $$ = make_str("exclusive"); }
+               | ACCESS EXCLUSIVE              { $$ = make_str("access exclusive"); }
+               ;
 
 /*****************************************************************************
  *