Fix for BUG#20188 "REPLACE or ON DUPLICATE KEY UPDATE in
auto_increment breaks binlog": if slave's table had a higher auto_increment counter than master's (even though all rows of the two tables were identical), then in some cases, REPLACE and INSERT ON DUPLICATE KEY UPDATE failed to replicate statement-based (it inserted different values on slave from on master). write_record() contained a "thd->next_insert_id=0" to force an adjustment of thd->next_insert_id after the update or replacement. But it is this assigment introduced indeterminism of the statement on the slave, thus the bug. For ON DUPLICATE, we replace that assignment by a call to handler::adjust_next_insert_id_after_explicit_value() which is deterministic (does not depend on slave table's autoinc counter). For REPLACE, this assignment can simply be removed (as REPLACE can't insert a number larger than thd->next_insert_id). We also move a too early restore_auto_increment() down to when we really know that we can restore the value. mysql-test/r/rpl_insert_id.result: result update, without the bugfix, slave's "3 350" were "4 350". mysql-test/t/rpl_insert_id.test: test for BUG#20188 "REPLACE or ON DUPLICATE KEY UPDATE in auto_increment breaks binlog". There is, in this order: - a test of the bug for the case of REPLACE - a test of basic ON DUPLICATE KEY UPDATE functionality which was not tested before - a test of the bug for the case of ON DUPLICATE KEY UPDATE sql/handler.cc: the adjustment of next_insert_id if inserting a big explicit value, is moved to a separate method to be used elsewhere. sql/handler.h: see handler.cc sql/sql_insert.cc: restore_auto_increment() means "I know I won't use this autogenerated autoincrement value, you are free to reuse it for next row". But we were calling restore_auto_increment() in the case of REPLACE: if write_row() fails inserting the row, we don't know that we won't use the value, as we are going to try again by doing internally an UPDATE of the existing row, or a DELETE of the existing row and then an INSERT. So I move restore_auto_increment() further down, when we know for sure we failed all possibilities for the row. Additionally, in case of REPLACE, we don't need to reset THD::next_insert_id: the value of thd->next_insert_id will be suitable for the next row. In case of ON DUPLICATE KEY UPDATE, resetting thd->next_insert_id is also wrong (breaks statement-based binlog), but cannot simply be removed, as thd->next_insert_id must be adjusted if the explicit value exceeds it. We now do the adjustment by calling handler::adjust_next_insert_id_after_explicit_value() (which, contrary to thd->next_insert_id=0, does not depend on the slave table's autoinc counter, and so is deterministic).
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