--source include/have_debug.inc
--source include/have_debug_sync.inc

--echo # Testing of histogram statistics that uses DEBUG functionality.

--echo #
--echo # Simulate a failure due to dropping histograms during DROP TABLE
--echo #
CREATE TABLE t1 (col1 INT, col2 INT);
ANALYZE TABLE t1 UPDATE HISTOGRAM ON col1, col2 WITH 10 BUCKETS;
SELECT schema_name, table_name, column_name
FROM information_schema.COLUMN_STATISTICS;

SELECT schema_name, table_name, column_name
FROM information_schema.COLUMN_STATISTICS;
SELECT COUNT(*) FROM information_schema.TABLES
WHERE TABLE_SCHEMA = 'test' AND TABLE_NAME = 't1';

SET DEBUG='+d,fail_after_drop_histograms';
--error ER_UNABLE_TO_DROP_COLUMN_STATISTICS
DROP TABLE t1;

SELECT schema_name, table_name, column_name
FROM information_schema.COLUMN_STATISTICS;
SELECT COUNT(*) FROM information_schema.TABLES
WHERE TABLE_SCHEMA = 'test' AND TABLE_NAME = 't1';

SET DEBUG='-d,fail_after_drop_histograms';

--echo #
--echo # Simulate a failure due to dropping histograms during ALTER TABLE
--echo #

SELECT schema_name, table_name, column_name
FROM information_schema.COLUMN_STATISTICS;
SELECT COUNT(*) FROM information_schema.COLUMNS
WHERE TABLE_SCHEMA = 'test' AND TABLE_NAME = 't1' AND COLUMN_NAME = 'col2';

SET DEBUG='+d,fail_after_drop_histograms';
--error ER_UNABLE_TO_DROP_COLUMN_STATISTICS
ALTER TABLE t1 DROP COLUMN col2;

SELECT schema_name, table_name, column_name
FROM information_schema.COLUMN_STATISTICS;
SELECT COUNT(*) FROM information_schema.COLUMNS
WHERE TABLE_SCHEMA = 'test' AND TABLE_NAME = 't1' AND COLUMN_NAME = 'col2';

SET DEBUG='-d,fail_after_drop_histograms';

--echo #
--echo # Simulate a failure due to renaming histograms during ALTER TABLE RENAME
--echo #
SELECT schema_name, table_name, column_name
FROM information_schema.COLUMN_STATISTICS;
SELECT COUNT(*) FROM information_schema.TABLES
WHERE TABLE_SCHEMA = 'test' AND TABLE_NAME = 't1';

SET DEBUG='+d,fail_after_rename_histograms';
--error ER_UNABLE_TO_UPDATE_COLUMN_STATISTICS
ALTER TABLE t1 RENAME TO t2;
SELECT schema_name, table_name, column_name
FROM information_schema.COLUMN_STATISTICS;
SELECT COUNT(*) FROM information_schema.TABLES
WHERE TABLE_SCHEMA = 'test' AND TABLE_NAME = 't1';
SET DEBUG='-d,fail_after_rename_histograms';

DROP TABLE t1;


--echo #
--echo # Check that histogram with sampling works as expected
--echo #

SET DEBUG='+d,histogram_force_sampling';

CREATE TABLE t1 (col1 DOUBLE);
INSERT INTO t1 SELECT RAND(1);
INSERT INTO t1 SELECT RAND(2) FROM t1;
INSERT INTO t1 SELECT RAND(3) FROM t1;
INSERT INTO t1 SELECT RAND(4) FROM t1;
INSERT INTO t1 SELECT RAND(5) FROM t1;
INSERT INTO t1 SELECT RAND(6) FROM t1;
INSERT INTO t1 SELECT RAND(7) FROM t1;
INSERT INTO t1 SELECT RAND(8) FROM t1;
INSERT INTO t1 SELECT RAND(9) FROM t1;
INSERT INTO t1 SELECT RAND(10) FROM t1;

ANALYZE TABLE t1 UPDATE HISTOGRAM ON col1 WITH 4 BUCKETS;
SELECT schema_name, table_name, column_name,
       JSON_REMOVE(histogram, '$."last-updated"')
FROM information_schema.COLUMN_STATISTICS;

SET DEBUG='-d,histogram_force_sampling';
DROP TABLE t1;

--echo #
--echo # Bug#26020352 WL8943:ASSERTION `M_THD->GET_TRANSACTION()->IS_EMPTY(
--echo #              TRANSACTION_CTX::STMT) && M
--echo #
CREATE TABLE t1 (col1 INT);
ANALYZE TABLE t1 UPDATE HISTOGRAM ON col1 WITH 10 BUCKETS;
SELECT schema_name, table_name, column_name
FROM information_schema.COLUMN_STATISTICS;
SET DEBUG='+d,histogram_fail_after_open_table';
ANALYZE TABLE t1 UPDATE HISTOGRAM ON col1 WITH 10 BUCKETS;
SELECT schema_name, table_name, column_name
FROM information_schema.COLUMN_STATISTICS;
SET DEBUG='-d,histogram_fail_after_open_table';
DROP TABLE t1;

--echo #
--echo # Bug#26027240 WL8943:VIRTUAL BOOL SQL_CMD_ANALYZE_TABLE::EXECUTE(THD*):
--echo #              ASSERTION `FALSE' FAIL
--echo #
CREATE TABLE t1 (col1 INT);
ANALYZE TABLE t1 UPDATE HISTOGRAM ON col1 WITH 10 BUCKETS;
SET DEBUG='+d,histogram_fail_during_lock_for_write';
ANALYZE TABLE t1 DROP HISTOGRAM ON col1;

--echo # Since we have simulated a fail, the histogram should still be present.
--echo # However, since this is a simulation of failure no error is reported.
SELECT schema_name, table_name, column_name
FROM information_schema.COLUMN_STATISTICS;
SET DEBUG='-d,histogram_fail_during_lock_for_write';
ANALYZE TABLE t1 DROP HISTOGRAM ON col1;

--echo # The histogram should now be gone.
SELECT schema_name, table_name, column_name
FROM information_schema.COLUMN_STATISTICS;
DROP TABLE t1;


--echo #
--echo # Bug#26772858 MDL FOR COLUMN STATISTICS IS NOT PROPERLY REFLECTED IN
--echo # P_S.METADATA_LOCKS
--echo #
connect(con1, localhost, root,,);
CREATE TABLE t1 (col1 INT);
SET DEBUG_SYNC='store_histogram_after_write_lock SIGNAL histogram_1_waiting WAIT_FOR continue_store_histogram';
--send ANALYZE TABLE t1 UPDATE HISTOGRAM ON col1 WITH 2 BUCKETS;

# The connection 'con1' will now wait on the debug sync point
# "store_histogram_after_write_lock", where it has acquired an exclusive lock
# on the histogram object. Switch connection, and inspect the metadata locks
# table in performance schema in order to verify that OBJECT_TYPE is properly
# reflected. Wait until 'con1' has signaled that it actually is waiting
--connection default
SET DEBUG_SYNC='now WAIT_FOR histogram_1_waiting';
SELECT OBJECT_TYPE, OBJECT_SCHEMA, OBJECT_NAME, COLUMN_NAME
  FROM performance_schema.metadata_locks
  WHERE LOCK_TYPE = "EXCLUSIVE"
    AND OBJECT_TYPE = "COLUMN STATISTICS"
  ORDER BY OBJECT_TYPE, OBJECT_SCHEMA, OBJECT_NAME, COLUMN_NAME;

# While 'con1' still is waiting on the sync point right after the exclusive lock
# is aquired, open a new connection and create a histogram for the same column.
# The effect we want is a wait on the same MDL, so that we can inspect that
# the lock is fully reflected in performance_schema.events_waits_*
connect(con2, localhost, root,,);
SET DEBUG_SYNC='mdl_acquire_lock_wait SIGNAL histogram_2_lock_waiting';
--send ANALYZE TABLE t1 UPDATE HISTOGRAM ON col1 WITH 2 BUCKETS;

# Go back to the default connection, and verify the contents of
# performance_schema.events_waits_*. Wait until 'con2' has signaled that it is
# actually waiting for the lock.
--connection default
SET DEBUG_SYNC='now WAIT_FOR histogram_2_lock_waiting';
SELECT OBJECT_TYPE, OBJECT_SCHEMA, OBJECT_NAME, INDEX_NAME
  FROM performance_schema.events_waits_current
  WHERE OBJECT_TYPE = "COLUMN STATISTICS"
  ORDER BY OBJECT_TYPE, OBJECT_SCHEMA, OBJECT_NAME, INDEX_NAME;

# Finally let 'con1' finish building the histogram. Once 'con1' has released the
# MDL on the column statistics object, 'con2' will continue and do its work.
SET DEBUG_SYNC='now SIGNAL continue_store_histogram';

--connection con1
--reap
--disconnect con1
--source include/wait_until_disconnected.inc

--connection con2
--reap
--disconnect con2
--source include/wait_until_disconnected.inc

--connection default
DROP TABLE t1;

--echo #
--echo # Bug#27672693  HISTOGRAMS: ASSERTION FAILED: !THD->TX_READ_ONLY
--echo #
CREATE TABLE t1(col1 INT);
SET LOCAL TRANSACTION READ ONLY;
--error ER_CANT_EXECUTE_IN_READ_ONLY_TRANSACTION
INSERT INTO t1 (col1) VALUES (1);
ANALYZE TABLE t1 UPDATE HISTOGRAM ON col1 WITH 16 BUCKETS;
SET LOCAL TRANSACTION READ WRITE;
INSERT INTO t1 (col1) VALUES (1);
ANALYZE TABLE t1 UPDATE HISTOGRAM ON col1 WITH 16 BUCKETS;
DROP TABLE t1;