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--echo #
--echo # Test of the case when two rewrite rule pattern have the same digest.
--echo #
SET sql_mode = concat ( @@sql_mode, ',PIPES_AS_CONCAT' );
--source suite/query_rewrite_plugins/include/have_plugin_rewriter.inc
CREATE TABLE t1 ( a VARCHAR(10) );
--source suite/query_rewrite_plugins/include/install_rewriter_with_optional_columns.inc
--echo # This will supposedly fill up the token buffer.
--echo # We have to keep entries in the error log unique, we can't clear it.
SET @query_term = 'SELECT * FROM test.t1 WHERE a = "digest_collision.test"';
SET @a_union_branch = ' UNION ' || @query_term;
SET @tail1 = 'UNION SELECT 1';
SET @tail2 = 'UNION SELECT 2';
SELECT character_maximum_length INTO @max_pattern_length
FROM information_schema.columns
WHERE table_name = 'rewrite_rules'
AND column_name = 'pattern';
SET @no_unions_that_fit =
floor(
( @max_pattern_length - char_length(@query_term) - char_length(@tail1) ) /
char_length(@a_union_branch));
SELECT @query_term, @a_union_branch, @max_pattern_length, @no_unions_that_fit;
SET @pattern1 = @query_term || repeat( @a_union_branch, @no_unions_that_fit);
SET @pattern2 = concat ( @pattern1, @tail1 );
SET @nonmatching_query = concat ( @pattern1, @tail2 );
INSERT INTO query_rewrite.rewrite_rules ( pattern, replacement )
VALUES ( @pattern1, 'SELECT "Rewrite rule #1"' ),
( @pattern2, 'SELECT "Rewrite rule #2"' );
CALL query_rewrite.flush_rewrite_rules();
SELECT group_concat(replacement) =
'SELECT "Rewrite rule #1",SELECT "Rewrite rule #2"'
AS digests_indeed_collide
FROM query_rewrite.rewrite_rules
GROUP BY pattern_digest;
SELECT char_length(pattern) FROM query_rewrite.rewrite_rules;
PREPARE pattern1_stmt FROM @pattern1;
EXECUTE pattern1_stmt;
PREPARE pattern2_stmt FROM @pattern2;
EXECUTE pattern2_stmt;
SET @@global.rewriter_verbose = 2;
PREPARE nonmatching_stmt FROM @nonmatching_query;
EXECUTE nonmatching_stmt;
SET @@global.rewriter_verbose = DEFAULT;
--source suite/query_rewrite_plugins/include/load_error_log.inc
SELECT search_error_log( '[Note]', '%Plugin Rewriter reported: ''Statement "SELECT * FROM test.t1 ' ||
'WHERE a = "digest_collision.test"%' );
DROP TABLE t1;
--source suite/query_rewrite_plugins/include/uninstall_rewriter.inc
--source suite/query_rewrite_plugins/include/drop_error_log.inc
SET sql_mode = DEFAULT;
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