Hi
I am sending updated version - the changes against last patch are two. I
use pg_terminate_backed for killing other terminates like Tom proposed. I
am not sure if it is 100% practical - on second hand the necessary right to
kill other sessions is almost available - and consistency with
pg_terminal_backend has sense. More - native implementation is
significantly better then solution implemented outer. I fixed docs little
bit - the timeout for logout (as reaction on SIGTERM is only 5 sec).
Regards
Pavel
diff --git a/doc/src/sgml/ref/drop_database.sgml b/doc/src/sgml/ref/drop_database.sgml
index 3ac06c984a..11a31899d2 100644
--- a/doc/src/sgml/ref/drop_database.sgml
+++ b/doc/src/sgml/ref/drop_database.sgml
@@ -21,7 +21,11 @@ PostgreSQL documentation
<refsynopsisdiv>
<synopsis>
-DROP DATABASE [ IF EXISTS ] <replaceable class="parameter">name</replaceable>
+DROP DATABASE [ ( <replaceable class="parameter">option</replaceable> [, ...] ) ] [ IF EXISTS ] <replaceable class="parameter">name</replaceable>
+
+<phrase>where <replaceable class="parameter">option</replaceable> can be one of:</phrase>
+
+ FORCE
</synopsis>
</refsynopsisdiv>
@@ -32,9 +36,11 @@ DROP DATABASE [ IF EXISTS ] <replaceable class="parameter">name</replaceable>
<command>DROP DATABASE</command> drops a database. It removes the
catalog entries for the database and deletes the directory
containing the data. It can only be executed by the database owner.
- Also, it cannot be executed while you or anyone else are connected
- to the target database. (Connect to <literal>postgres</literal> or any
- other database to issue this command.)
+ Also, it cannot be executed while you are connected to the target database.
+ (Connect to <literal>postgres</literal> or any other database to issue this
+ command.)
+ If anyone else is connected to the target database, this command will fail
+ - unless you use the <literal>FORCE</literal> option described below.
</para>
<para>
@@ -64,6 +70,24 @@ DROP DATABASE [ IF EXISTS ] <replaceable class="parameter">name</replaceable>
</para>
</listitem>
</varlistentry>
+
+ <varlistentry>
+ <term><literal>FORCE</literal></term>
+ <listitem>
+ <para>
+ Attempt to terminate all existing connections to the target database.
+ </para>
+ <para>
+ This will fail, if current user has no permissions to terminate other
+ connections. Required permissions are the same as with
+ <literal>pg_terminate_backend</literal>, described
+ in <xref linkend="functions-admin-signal"/>.
+
+ This will also fail, if the connections do not terminate in 5 seconds.
+ </para>
+ </listitem>
+ </varlistentry>
+
</variablelist>
</refsect1>
diff --git a/doc/src/sgml/ref/dropdb.sgml b/doc/src/sgml/ref/dropdb.sgml
index 3fbdb33716..5d10ad1c92 100644
--- a/doc/src/sgml/ref/dropdb.sgml
+++ b/doc/src/sgml/ref/dropdb.sgml
@@ -86,6 +86,20 @@ PostgreSQL documentation
</listitem>
</varlistentry>
+ <varlistentry>
+ <term><option>-f</option></term>
+ <term><option>--force</option></term>
+ <listitem>
+ <para>
+ Force termination of connected backends before removing the database.
+ </para>
+ <para>
+ This will add the <literal>FORCE</literal> option to the <literal>DROP
+ DATABASE</literal> command sent to the server.
+ </para>
+ </listitem>
+ </varlistentry>
+
<varlistentry>
<term><option>-V</option></term>
<term><option>--version</option></term>
diff --git a/src/backend/commands/dbcommands.c b/src/backend/commands/dbcommands.c
index 95881a8550..faa5bdbf71 100644
--- a/src/backend/commands/dbcommands.c
+++ b/src/backend/commands/dbcommands.c
@@ -810,7 +810,7 @@ createdb_failure_callback(int code, Datum arg)
* DROP DATABASE
*/
void
-dropdb(const char *dbname, bool missing_ok)
+dropdb(const char *dbname, bool missing_ok, bool force)
{
Oid db_id;
bool db_istemplate;
@@ -895,6 +895,9 @@ dropdb(const char *dbname, bool missing_ok)
nslots_active, nslots_active)));
}
+ if (force)
+ TerminateOtherDBBackends(db_id);
+
/*
* Check for other backends in the target database. (Because we hold the
* database lock, no new ones can start after this.)
diff --git a/src/backend/nodes/copyfuncs.c b/src/backend/nodes/copyfuncs.c
index 3432bb921d..2f267e4bb6 100644
--- a/src/backend/nodes/copyfuncs.c
+++ b/src/backend/nodes/copyfuncs.c
@@ -3868,6 +3868,7 @@ _copyDropdbStmt(const DropdbStmt *from)
COPY_STRING_FIELD(dbname);
COPY_SCALAR_FIELD(missing_ok);
+ COPY_NODE_FIELD(options);
return newnode;
}
diff --git a/src/backend/nodes/equalfuncs.c b/src/backend/nodes/equalfuncs.c
index 18cb014373..da0e1d139a 100644
--- a/src/backend/nodes/equalfuncs.c
+++ b/src/backend/nodes/equalfuncs.c
@@ -1676,6 +1676,7 @@ _equalDropdbStmt(const DropdbStmt *a, const DropdbStmt *b)
{
COMPARE_STRING_FIELD(dbname);
COMPARE_SCALAR_FIELD(missing_ok);
+ COMPARE_NODE_FIELD(options);
return true;
}
diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index 3f67aaf30e..f7bab61175 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -310,6 +310,7 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
%type <defelt> vac_analyze_option_elem
%type <list> vac_analyze_option_list
%type <node> vac_analyze_option_arg
+%type <defelt> drop_option
%type <boolean> opt_or_replace
opt_grant_grant_option opt_grant_admin_option
opt_nowait opt_if_exists opt_with_data
@@ -406,6 +407,7 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
TriggerTransitions TriggerReferencing
publication_name_list
vacuum_relation_list opt_vacuum_relation_list
+ drop_option_list opt_drop_option_list
%type <list> group_by_list
%type <node> group_by_item empty_grouping_set rollup_clause cube_clause
@@ -10213,27 +10215,56 @@ AlterDatabaseSetStmt:
/*****************************************************************************
*
- * DROP DATABASE [ IF EXISTS ]
+ * DROP DATABASE [ ( FORCE ) ] [ IF EXISTS ]
*
* This is implicitly CASCADE, no need for drop behavior
*****************************************************************************/
-DropdbStmt: DROP DATABASE database_name
+DropdbStmt: DROP DATABASE opt_drop_option_list database_name
{
DropdbStmt *n = makeNode(DropdbStmt);
- n->dbname = $3;
+ n->dbname = $4;
n->missing_ok = false;
+ n->options = $3;
$$ = (Node *)n;
}
- | DROP DATABASE IF_P EXISTS database_name
+ | DROP DATABASE opt_drop_option_list IF_P EXISTS database_name
{
DropdbStmt *n = makeNode(DropdbStmt);
- n->dbname = $5;
+ n->dbname = $6;
n->missing_ok = true;
+ n->options = $3;
$$ = (Node *)n;
}
;
+opt_drop_option_list:
+ '(' drop_option_list ')'
+ {
+ $$ = $2;
+ }
+ | /* EMPTY */
+ {
+ $$ = NIL;
+ }
+ ;
+
+drop_option_list:
+ drop_option
+ {
+ $$ = list_make1((Node *) $1);
+ }
+ | drop_option_list ',' drop_option
+ {
+ $$ = lappend($1, (Node *) $3);
+ }
+ ;
+
+drop_option: FORCE
+ {
+ $$ = makeDefElem("force", NULL, @1);
+ }
+ ;
/*****************************************************************************
*
diff --git a/src/backend/storage/ipc/procarray.c b/src/backend/storage/ipc/procarray.c
index 8abcfdf841..035fc2628c 100644
--- a/src/backend/storage/ipc/procarray.c
+++ b/src/backend/storage/ipc/procarray.c
@@ -2970,6 +2970,50 @@ CountOtherDBBackends(Oid databaseId, int *nbackends, int *nprepared)
return true; /* timed out, still conflicts */
}
+/*
+ * Terminate other db connections
+ */
+void
+TerminateOtherDBBackends(Oid databaseId)
+{
+ ProcArrayStruct *arrayP = procArray;
+ List *pids = NIL;
+ int i;
+
+ LWLockAcquire(ProcArrayLock, LW_SHARED);
+
+ for (i = 0; i < procArray->numProcs; i++)
+ {
+ int pgprocno = arrayP->pgprocnos[i];
+ PGPROC *proc = &allProcs[pgprocno];
+
+ if (proc->databaseId != databaseId)
+ continue;
+ if (proc == MyProc)
+ continue;
+
+ if (proc->pid != 0)
+ pids = lappend_int(pids, proc->pid);
+ }
+
+ LWLockRelease(ProcArrayLock);
+
+ if (pids)
+ {
+ ListCell *lc;
+
+ foreach (lc, pids)
+ {
+ int pid = lfirst_int(lc);
+
+ (void) DirectFunctionCall1(pg_terminate_backend, Int32GetDatum(pid));
+ }
+
+ /* sleep 100ms */
+ pg_usleep(100 * 1000L);
+ }
+}
+
/*
* ProcArraySetReplicationSlotXmin
*
diff --git a/src/backend/tcop/utility.c b/src/backend/tcop/utility.c
index c6faa6619d..d69e30972f 100644
--- a/src/backend/tcop/utility.c
+++ b/src/backend/tcop/utility.c
@@ -598,10 +598,20 @@ standard_ProcessUtility(PlannedStmt *pstmt,
case T_DropdbStmt:
{
DropdbStmt *stmt = (DropdbStmt *) parsetree;
+ bool force = false;
+ ListCell *lc;
+
+ foreach(lc, stmt->options)
+ {
+ DefElem *item = (DefElem *) lfirst(lc);
+
+ if (strcmp(item->defname, "force") == 0)
+ force = true;
+ }
/* no event triggers for global objects */
PreventInTransactionBlock(isTopLevel, "DROP DATABASE");
- dropdb(stmt->dbname, stmt->missing_ok);
+ dropdb(stmt->dbname, stmt->missing_ok, force);
}
break;
diff --git a/src/bin/scripts/dropdb.c b/src/bin/scripts/dropdb.c
index dacd8e5f1d..8bac1faa42 100644
--- a/src/bin/scripts/dropdb.c
+++ b/src/bin/scripts/dropdb.c
@@ -34,6 +34,7 @@ main(int argc, char *argv[])
{"interactive", no_argument, NULL, 'i'},
{"if-exists", no_argument, &if_exists, 1},
{"maintenance-db", required_argument, NULL, 2},
+ {"force", no_argument, NULL, 'f'},
{NULL, 0, NULL, 0}
};
@@ -49,6 +50,7 @@ main(int argc, char *argv[])
enum trivalue prompt_password = TRI_DEFAULT;
bool echo = false;
bool interactive = false;
+ bool force = false;
PQExpBufferData sql;
@@ -61,7 +63,7 @@ main(int argc, char *argv[])
handle_help_version_opts(argc, argv, "dropdb", help);
- while ((c = getopt_long(argc, argv, "h:p:U:wWei", long_options, &optindex)) != -1)
+ while ((c = getopt_long(argc, argv, "h:p:U:wWeif", long_options, &optindex)) != -1)
{
switch (c)
{
@@ -86,6 +88,9 @@ main(int argc, char *argv[])
case 'i':
interactive = true;
break;
+ case 'f':
+ force = true;
+ break;
case 0:
/* this covers the long options */
break;
@@ -123,9 +128,6 @@ main(int argc, char *argv[])
initPQExpBuffer(&sql);
- appendPQExpBuffer(&sql, "DROP DATABASE %s%s;",
- (if_exists ? "IF EXISTS " : ""), fmtId(dbname));
-
/* Avoid trying to drop postgres db while we are connected to it. */
if (maintenance_db == NULL && strcmp(dbname, "postgres") == 0)
maintenance_db = "template1";
@@ -134,6 +136,10 @@ main(int argc, char *argv[])
host, port, username, prompt_password,
progname, echo);
+ appendPQExpBuffer(&sql, "DROP DATABASE %s%s%s;",
+ (force ? " (FORCE) " : ""),
+ (if_exists ? "IF EXISTS " : ""), fmtId(dbname));
+
if (echo)
printf("%s\n", sql.data);
result = PQexec(conn, sql.data);
@@ -159,6 +165,7 @@ help(const char *progname)
printf(_("\nOptions:\n"));
printf(_(" -e, --echo show the commands being sent to the server\n"));
printf(_(" -i, --interactive prompt before deleting anything\n"));
+ printf(_(" -f, --force force termination of connected backends\n"));
printf(_(" -V, --version output version information, then exit\n"));
printf(_(" --if-exists don't report error if database doesn't exist\n"));
printf(_(" -?, --help show this help, then exit\n"));
diff --git a/src/bin/scripts/t/050_dropdb.pl b/src/bin/scripts/t/050_dropdb.pl
index 25aa54a4ae..8e1899a6c5 100644
--- a/src/bin/scripts/t/050_dropdb.pl
+++ b/src/bin/scripts/t/050_dropdb.pl
@@ -3,7 +3,7 @@ use warnings;
use PostgresNode;
use TestLib;
-use Test::More tests => 11;
+use Test::More tests => 13;
program_help_ok('dropdb');
program_version_ok('dropdb');
@@ -19,5 +19,11 @@ $node->issues_sql_like(
qr/statement: DROP DATABASE foobar1/,
'SQL DROP DATABASE run');
+$node->safe_psql('postgres', 'CREATE DATABASE foobar2');
+$node->issues_sql_like(
+ [ 'dropdb', '--force', 'foobar2' ],
+ qr/statement: DROP DATABASE (FORCE) foobar2/,
+ 'SQL DROP DATABASE (FORCE) run');
+
$node->command_fails([ 'dropdb', 'nonexistent' ],
'fails with nonexistent database');
diff --git a/src/include/commands/dbcommands.h b/src/include/commands/dbcommands.h
index 154c8157ee..66e0b904bf 100644
--- a/src/include/commands/dbcommands.h
+++ b/src/include/commands/dbcommands.h
@@ -20,7 +20,7 @@
#include "nodes/parsenodes.h"
extern Oid createdb(ParseState *pstate, const CreatedbStmt *stmt);
-extern void dropdb(const char *dbname, bool missing_ok);
+extern void dropdb(const char *dbname, bool missing_ok, bool force);
extern ObjectAddress RenameDatabase(const char *oldname, const char *newname);
extern Oid AlterDatabase(ParseState *pstate, AlterDatabaseStmt *stmt, bool isTopLevel);
extern Oid AlterDatabaseSet(AlterDatabaseSetStmt *stmt);
diff --git a/src/include/nodes/parsenodes.h b/src/include/nodes/parsenodes.h
index d93a79a554..ff626cbe61 100644
--- a/src/include/nodes/parsenodes.h
+++ b/src/include/nodes/parsenodes.h
@@ -3145,6 +3145,7 @@ typedef struct DropdbStmt
NodeTag type;
char *dbname; /* database to drop */
bool missing_ok; /* skip error if db is missing? */
+ List *options; /* currently only FORCE is supported */
} DropdbStmt;
/* ----------------------
diff --git a/src/include/storage/procarray.h b/src/include/storage/procarray.h
index da8b672096..e82f6c7c98 100644
--- a/src/include/storage/procarray.h
+++ b/src/include/storage/procarray.h
@@ -111,8 +111,8 @@ extern int CountDBBackends(Oid databaseid);
extern int CountDBConnections(Oid databaseid);
extern void CancelDBBackends(Oid databaseid, ProcSignalReason sigmode, bool conflictPending);
extern int CountUserBackends(Oid roleid);
-extern bool CountOtherDBBackends(Oid databaseId,
- int *nbackends, int *nprepared);
+extern bool CountOtherDBBackends(Oid databaseId, int *nbackends, int *nprepared);
+extern void TerminateOtherDBBackends(Oid databaseId);
extern void XidCacheRemoveRunningXids(TransactionId xid,
int nxids, const TransactionId *xids,
