From f3985c649d65c2d932a6f74d22de3d2e6624d525 Mon Sep 17 00:00:00 2001 From: Sven Sandberg Date: Tue, 14 Jul 2009 21:31:19 +0200 Subject: BUG#39934: Slave stops for engine that only support row-based logging General overview: The logic for switching to row format when binlog_format=MIXED had numerous flaws. The underlying problem was the lack of a consistent architecture. General purpose of this changeset: This changeset introduces an architecture for switching to row format when binlog_format=MIXED. It enforces the architecture where it has to. It leaves some bugs to be fixed later. It adds extensive tests to verify that unsafe statements work as expected and that appropriate errors are produced by problems with the selection of binlog format. It was not practical to split this into smaller pieces of work. Problem 1: To determine the logging mode, the code has to take several parameters into account (namely: (1) the value of binlog_format; (2) the capabilities of the engines; (3) the type of the current statement: normal, unsafe, or row injection). These parameters may conflict in several ways, namely: - binlog_format=STATEMENT for a row injection - binlog_format=STATEMENT for an unsafe statement - binlog_format=STATEMENT for an engine only supporting row logging - binlog_format=ROW for an engine only supporting statement logging - statement is unsafe and engine does not support row logging - row injection in a table that does not support statement logging - statement modifies one table that does not support row logging and one that does not support statement logging Several of these conflicts were not detected, or were detected with an inappropriate error message. The problem of BUG#39934 was that no appropriate error message was written for the case when an engine only supporting row logging executed a row injection with binlog_format=ROW. However, all above cases must be handled. Fix 1: Introduce new error codes (sql/share/errmsg.txt). Ensure that all conditions are detected and handled in decide_logging_format() Problem 2: The binlog format shall be determined once per statement, in decide_logging_format(). It shall not be changed before or after that. Before decide_logging_format() is called, all information necessary to determine the logging format must be available. This principle ensures that all unsafe statements are handled in a consistent way. However, this principle is not followed: thd->set_current_stmt_binlog_row_based_if_mixed() is called in several places, including from code executing UPDATE..LIMIT, INSERT..SELECT..LIMIT, DELETE..LIMIT, INSERT DELAYED, and SET @@binlog_format. After Problem 1 was fixed, that caused inconsistencies where these unsafe statements would not print the appropriate warnings or errors for some of the conflicts. Fix 2: Remove calls to THD::set_current_stmt_binlog_row_based_if_mixed() from code executed after decide_logging_format(). Compensate by calling the set_current_stmt_unsafe() at parse time. This way, all unsafe statements are detected by decide_logging_format(). Problem 3: INSERT DELAYED is not unsafe: it is logged in statement format even if binlog_format=MIXED, and no warning is printed even if binlog_format=STATEMENT. This is BUG#45825. Fix 3: Made INSERT DELAYED set itself to unsafe at parse time. This allows decide_logging_format() to detect that a warning should be printed or the binlog_format changed. Problem 4: LIMIT clause were not marked as unsafe when executed inside stored functions/triggers/views/prepared statements. This is BUG#45785. Fix 4: Make statements containing the LIMIT clause marked as unsafe at parse time, instead of at execution time. This allows propagating unsafe-ness to the view. --- sql/sp_head.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'sql/sp_head.h') diff --git a/sql/sp_head.h b/sql/sp_head.h index dd11f8693ac..7faccb7afbb 100644 --- a/sql/sp_head.h +++ b/sql/sp_head.h @@ -459,6 +459,7 @@ public: */ void propagate_attributes(LEX *lex) { + DBUG_ENTER("sp_head::propagate_attributes"); /* If this routine needs row-based binary logging, the entire top statement too (we cannot switch from statement-based to row-based only for this @@ -467,6 +468,7 @@ public: */ if (m_flags & BINLOG_ROW_BASED_IF_MIXED) lex->set_stmt_unsafe(); + DBUG_VOID_RETURN; } -- cgit v1.2.1 From 931ac1d7812daffbf499757e413e148094775866 Mon Sep 17 00:00:00 2001 From: Sven Sandberg Date: Wed, 22 Jul 2009 18:16:17 +0200 Subject: BUG#39934: Slave stops for engine that only support row-based logging This is a post-push fix addressing review requests and problems with extra warnings. Problem 1: The sub-statement where an unsafe warning was detected was printed as part of the warning. This was ok for statements that were unsafe due to, e.g., calls to UUID(), but did not make sense for statements that were unsafe because there was more than one autoincrement column (unsafeness in this case comes from the combination of several sub-statements). Fix 1: Instead of printing the sub-statement, print an explanation of why the statement is unsafe. Problem 2: When a recursive construct (i.e., stored proceure, stored function, trigger, view, prepared statement) contained several sub-statements, and at least one of them was unsafe, there would be one unsafeness warning per sub-statement - even for safe sub-statements. Fix 2: Ensure that each type of warning is printed at most once, by remembering throughout the execution of the statement which types of warnings have been printed. --- sql/sp_head.h | 22 ++++++++++++++-------- 1 file changed, 14 insertions(+), 8 deletions(-) (limited to 'sql/sp_head.h') diff --git a/sql/sp_head.h b/sql/sp_head.h index 7faccb7afbb..3de9abd6760 100644 --- a/sql/sp_head.h +++ b/sql/sp_head.h @@ -165,9 +165,8 @@ public: HAS_COMMIT_OR_ROLLBACK= 128, LOG_SLOW_STATEMENTS= 256, // Used by events LOG_GENERAL_LOG= 512, // Used by events - BINLOG_ROW_BASED_IF_MIXED= 1024, - HAS_SQLCOM_RESET= 2048, - HAS_SQLCOM_FLUSH= 4096 + HAS_SQLCOM_RESET= 1024, + HAS_SQLCOM_FLUSH= 2048 }; /** TYPE_ENUM_FUNCTION, TYPE_ENUM_PROCEDURE or TYPE_ENUM_TRIGGER */ @@ -198,6 +197,11 @@ public: private: Stored_program_creation_ctx *m_creation_ctx; + /** + Boolean combination of (1<set_stmt_unsafe(); + DBUG_PRINT("info", ("lex->get_stmt_unsafe_flags(): 0x%x", + lex->get_stmt_unsafe_flags())); + DBUG_PRINT("info", ("sp_head(0x%p=%s)->unsafe_flags: 0x%x", + this, name(), unsafe_flags)); + lex->set_stmt_unsafe_flags(unsafe_flags); DBUG_VOID_RETURN; } -- cgit v1.2.1