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================================================================================
SETUP
================================================================================
CREATE TABLE test.t1 (c1 INT);
PREPARE stmt1 FROM "SELECT c1 FROM test.t1";
EXECUTE stmt1;
c1
SHOW SESSION STATUS LIKE "%com_stmt_%prepare%";
Variable_name Value
Com_stmt_prepare 1
Com_stmt_reprepare 0
SELECT * FROM performance_schema.session_status WHERE VARIABLE_NAME LIKE "%com_stmt%";
VARIABLE_NAME VARIABLE_VALUE
Com_stmt_reprepare 0
SELECT VARIABLE_VALUE FROM performance_schema.global_status
WHERE VARIABLE_NAME LIKE "Com_stmt_reprepare"
INTO @count_global_reprepare_before;
ALTER TABLE test.t1 ADD COLUMN c2 INTEGER;
EXECUTE stmt1;
c1
SHOW SESSION STATUS LIKE "%com_stmt_%prepare%";
Variable_name Value
Com_stmt_prepare 2
Com_stmt_reprepare 1
SELECT * FROM performance_schema.session_status WHERE VARIABLE_NAME LIKE "%com_stmt%";
VARIABLE_NAME VARIABLE_VALUE
Com_stmt_reprepare 1
SELECT VARIABLE_VALUE FROM performance_schema.global_status
WHERE VARIABLE_NAME LIKE "Com_stmt_reprepare"
INTO @count_global_reprepare_after;
SELECT @count_global_reprepare_after - @count_global_reprepare_before;
@count_global_reprepare_after - @count_global_reprepare_before
1
================================================================================
CLEANUP
================================================================================
DROP TABLE test.t1;
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