Test, ensure pt-table-checksum can handle col names with dots.

t/pt-table-checksum/basics.t

@@ -41,7 +41,7 @@ elsif ( !@{$master_dbh->selectall_arrayref('show databases like "sakila"')} ) {
    plan skip_all => 'sakila database is not loaded';
 }
 else {
-   plan tests => 32;
+   plan tests => 35;
 }
 
 # The sandbox servers run with lock_wait_timeout=3 and it's not dynamic
@@ -420,6 +420,40 @@ is(
    "Bug 932442: 0 errors"
 );
 
+# #############################################################################
+# Bug 821675: can't parse column names containing periods
+# #############################################################################
+$sb->load_file('master', "t/pt-table-checksum/samples/dot.sql");
+PerconaTest::wait_for_table($master_dbh, "test.t", "`No.`='ten'");
+
+ok(
+   no_diff(
+      sub { pt_table_checksum::main(@args,
+         qw(-t test.t --chunk-size 3 --explain --explain))
+      },
+      "t/pt-table-checksum/samples/dot.out",
+   ),
+   "Bug 821675 (dot): queries"
+);
+
+$output = output(
+   sub { $exit_status = pt_table_checksum::main(@args,
+      qw(-t test.t --chunk-size 3 --explain --explain)) },
+   stderr => 1,
+);
+
+is(
+   $exit_status,
+   0,
+   "Bug 821675 (dot): 0 exit"
+);
+
+is(
+   PerconaTest::count_checksum_results($output, 'errors'),
+   0,
+   "Bug 821675 (dot): 0 errors"
+);
+
 # #############################################################################
 # Done.
 # #############################################################################

t/pt-table-checksum/samples/dot.out

@@ -0,0 +1,19 @@
+--
+-- test.t
+--
+
+REPLACE INTO `percona`.`checksums` (db, tbl, chunk, chunk_index, lower_boundary, upper_boundary, this_cnt, this_crc) SELECT ?, ?, ?, ?, ?, ?, COUNT(*) AS cnt, COALESCE(LOWER(CONV(BIT_XOR(CAST(CRC32(CONCAT_WS('#', `no.`, `foo.bar`, CONCAT(ISNULL(`foo.bar`)))) AS UNSIGNED)), 10, 16)), 0) AS crc FROM `test`.`t` FORCE INDEX(`PRIMARY`) WHERE ((`no.` >= ?)) AND ((`no.` <= ?)) /*checksum chunk*/
+
+REPLACE INTO `percona`.`checksums` (db, tbl, chunk, chunk_index, lower_boundary, upper_boundary, this_cnt, this_crc) SELECT ?, ?, ?, ?, ?, ?, COUNT(*), '0' FROM `test`.`t` FORCE INDEX(`PRIMARY`) WHERE ((`no.` < ?)) ORDER BY `no.` /*past lower chunk*/
+
+REPLACE INTO `percona`.`checksums` (db, tbl, chunk, chunk_index, lower_boundary, upper_boundary, this_cnt, this_crc) SELECT ?, ?, ?, ?, ?, ?, COUNT(*), '0' FROM `test`.`t` FORCE INDEX(`PRIMARY`) WHERE ((`no.` > ?)) ORDER BY `no.` /*past upper chunk*/
+
+SELECT /*!40001 SQL_NO_CACHE */ `no.` FROM `test`.`t` FORCE INDEX(`PRIMARY`) WHERE ((`no.` >= ?)) ORDER BY `no.` LIMIT ?, 2 /*next chunk boundary*/
+
+1 eight four
+2 nine seven
+3 six three
+4 two two
+5  eight
+6 two 
+

t/pt-table-checksum/samples/dot.sql

@@ -0,0 +1,21 @@
+drop database if exists test;
+create database test;
+use test;
+
+CREATE TABLE t (
+  `No.` varchar(16) NOT NULL DEFAULT '',
+  `foo.bar` varchar(16),
+  PRIMARY KEY (`No.`)
+) ENGINE=MyISAM;
+
+insert into t values
+  ('one', 'a'),
+  ('two', 'a'),
+  ('three', 'a'),
+  ('four', 'a'),
+  ('five', 'a'),
+  ('six', 'a'),
+  ('seven', 'a'),
+  ('eight', 'a'),
+  ('nine', 'a'),
+  ('ten', 'a');