From 5ec6043ac37380fac2cbcbc15e4f2e8b76653f15 Mon Sep 17 00:00:00 2001
From: Kristofer Pettersson <kristofer.pettersson@sun.com>
Date: Mon, 21 Sep 2009 11:58:15 +0200
Subject: [PATCH] Fix for BUG#35570 "CHECKSUM TABLE unreliable if LINESTRING
 field (same content/ differen checksum)"

The problem was that checksum of GEOMETRY type used memory addresses
in the computation, making it un-repeatable thus useless.
(This patch is a backport from 6.0 branch)

mysql-test/r/myisam.result:
  test case for bug35570 that same tables give same checksums
mysql-test/t/myisam.test:
  test case for bug35570 that same tables give same checksums
sql/sql_table.cc:
  Type GEOMETRY is implemented on top of type BLOB, so, just like for BLOB,
  its 'field' contains pointers which it does not make sense to include in
  the checksum; it rather has to be converted to a string and then we can
  compute the checksum.
---
 mysql-test/r/myisam.result | 19 +++++++++++++++++++
 mysql-test/t/myisam.test   | 15 +++++++++++++++
 sql/sql_table.cc           | 10 ++++++++--
 3 files changed, 42 insertions(+), 2 deletions(-)

diff --git a/mysql-test/r/myisam.result b/mysql-test/r/myisam.result
index 732b1b260f8..58e2e451a0d 100644
--- a/mysql-test/r/myisam.result
+++ b/mysql-test/r/myisam.result
@@ -2252,4 +2252,23 @@ h+0	d + 0	e	g + 0
 1	1	3	0
 1	1	4	0
 DROP TABLE t1;
+#
+# Test of BUG#35570 CHECKSUM TABLE unreliable if LINESTRING field
+# (same content / differen checksum)
+#
+CREATE TABLE t1 (line LINESTRING NOT NULL) engine=myisam;
+INSERT INTO t1 VALUES (GeomFromText("POINT(0 0)"));
+checksum table t1;
+Table	Checksum
+test.t1	326284887
+CREATE TABLE t2 (line LINESTRING NOT NULL) engine=myisam;
+INSERT INTO t2 VALUES (GeomFromText("POINT(0 0)"));
+checksum table t2;
+Table	Checksum
+test.t2	326284887
+CREATE TABLE t3 select * from t1;
+checksum table t3;
+Table	Checksum
+test.t3	326284887
+drop table t1,t2,t3;
 End of 5.1 tests
diff --git a/mysql-test/t/myisam.test b/mysql-test/t/myisam.test
index ba6bc05cfea..5de7c997a24 100644
--- a/mysql-test/t/myisam.test
+++ b/mysql-test/t/myisam.test
@@ -1503,5 +1503,20 @@ SELECT h+0, d + 0, e, g + 0 FROM t1;
 
 DROP TABLE t1;
 
+--echo #
+--echo # Test of BUG#35570 CHECKSUM TABLE unreliable if LINESTRING field
+--echo # (same content / differen checksum)
+--echo #
+
+CREATE TABLE t1 (line LINESTRING NOT NULL) engine=myisam;
+INSERT INTO t1 VALUES (GeomFromText("POINT(0 0)"));
+checksum table t1;
+CREATE TABLE t2 (line LINESTRING NOT NULL) engine=myisam;
+INSERT INTO t2 VALUES (GeomFromText("POINT(0 0)"));
+checksum table t2;
+CREATE TABLE t3 select * from t1;
+checksum table t3;
+drop table t1,t2,t3;
+
 --echo End of 5.1 tests
 
diff --git a/sql/sql_table.cc b/sql/sql_table.cc
index 9d929c0d1a3..08f3311be9d 100644
--- a/sql/sql_table.cc
+++ b/sql/sql_table.cc
@@ -7897,8 +7897,14 @@ bool mysql_checksum_table(THD *thd, TABLE_LIST *tables,
 	    for (uint i= 0; i < t->s->fields; i++ )
 	    {
 	      Field *f= t->field[i];
-	      if ((f->type() == MYSQL_TYPE_BLOB) ||
-                  (f->type() == MYSQL_TYPE_VARCHAR))
+        enum_field_types field_type= f->type();
+        /*
+          BLOB and VARCHAR have pointers in their field, we must convert
+          to string; GEOMETRY is implemented on top of BLOB.
+        */
+        if ((field_type == MYSQL_TYPE_BLOB) ||
+            (field_type == MYSQL_TYPE_VARCHAR) ||
+            (field_type == MYSQL_TYPE_GEOMETRY))
 	      {
 		String tmp;
 		f->val_str(&tmp);