1 files changed, 94 insertions, 0 deletions
diff --git a/tests/lock_test.pl b/tests/lock_test.pl
new file mode 100755
index 00000000000..5daeeddad8e
--- /dev/null
+++ b/tests/lock_test.pl
@@ -0,0 +1,94 @@
+#!/usr/bin/perl
+
+# This is a test with uses two processes to a database.
+# The other inserts records in two tables, the other does a lot of joins
+# on these.
+# Every time the read thread outputs info, it does a ALTER TABLE command
+# which should stop the insert thread until the ALTER TABLE command is ready.
+#
+# Warning, the output from this test will differ in 'found' from time to time,
+# but there should never be any errors
+#
+
+$host = shift || "";
+$test_db="test";
+$test_count=10000;
+srand 0;			# Repeatable test
+
+use Mysql;
+$|= 1;				# Autoflush
+
+$dbh = Mysql->Connect($host) || die "Can't connect: $Mysql::db_errstr\n";
+$dbh->SelectDB($test_db) || die "Can't use database $test_db: $Mysql::db_errstr\n";
+
+$firsttable  = "test_lock_1";
+$secondtable = "test_lock_2";
+$dbh->Query("drop table $firsttable");
+$dbh->Query("drop table $secondtable");
+
+print "Creating tables $firsttable and $secondtable in database $test_db\n";
+$dbh->Query("create table $firsttable (id int(6) not null, info char(32), auto int(11) not null auto_increment, primary key(id),key(auto))") or die $Mysql::db_errstr;
+
+$dbh->Query("create table $secondtable (id int(6) not null, info varchar(32), key(id))") or die $Mysql::db_errstr;
+
+$dbh=0;				# Close handler
+
+if (fork() == 0)
+{				# Insert process
+  $dbh = Mysql->Connect($host) || die "Can't connect: $Mysql::db_errstr\n";
+  $dbh->SelectDB($test_db) || die "Can't use database $test_db: $Mysql::db_errstr\n";
+  $first_id=1; $second_id=1;
+  $first_count=$second_count=0;
+  print "Writing started\n";
+  for ($i=1 ; $i <= $test_count ; $i++)
+  {
+    if (rand(3) <= 1)
+    {
+      $sth=$dbh->Query("insert into $firsttable values ($first_id,'This is entry $i',NULL)") || die "Got error on insert: $Mysql::db_errstr\n";
+      die "Row not inserted, aborting\n" if ($sth->affected_rows != 1);
+      $first_id++;
+      $first_count++;
+    }
+    else
+    {
+      $sth=$dbh->Query("insert into $secondtable values ($second_id,'This is entry $i')") || die "Got error on insert: $Mysql::db_errstr\n";
+      die "Row not inserted, aborting\n" if ($sth->affected_rows != 1);
+      $second_id++ if (rand(10) <= 1); # Don't always count it up
+      $second_count++;
+    }
+    print "Write: $i\n" if ($i % 1000 == 0);
+  }
+  print "Writing done ($first_count $second_count)\n";
+}
+else
+{
+  $dbh = Mysql->Connect($host) || die "Can't connect: $Mysql::db_errstr\n";
+  $dbh->SelectDB($test_db) || die "Can't use database $test_db: $Mysql::db_errstr\n";
+  $locked=$found=0;
+  print "Reading started\n";
+  for ($i=1 ; $i <= $test_count ; $i++)
+  {
+    $id=int(rand($test_count)/3)+1;
+    $sth=$dbh->Query("select count(*) from $firsttable,$secondtable where $firsttable.id = $secondtable.id and $firsttable.id=$id") || die "Got error on select: $Mysql::db_errstr\n";
+    $found++ if ($sth->numrows);
+    if ($i % 1000 == 0)
+    {
+      print "Read:  $i  Found: $found\n";
+      if ($found)
+      {
+	$locked=1-$locked;
+	if ($locked)
+	{
+	  $sth=$dbh->Query("lock tables $firsttable write,$secondtable write");
+	}
+	$sth=$dbh->Query("alter table $firsttable CHANGE id id int(6) not null") || die "Got error on ALTER TABLE: $Mysql::db_errstr\n";
+	$sth=$dbh->Query("alter table $secondtable CHANGE info info char(32) not null") || die "Got error on ALTER TABLE: $Mysql::db_errstr\n";
+	if ($locked)
+	{
+	  $sth=$dbh->Query("unlock tables");
+	}
+      }
+    }
+  }
+  print "Reading done  Found: $found\n";
+}