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[Maria-developers] MWL#39 improving mysqlbinlog output and doing rename
by Michael Widenius 17 Aug '09

17 Aug '09

Hi! >>>>> "Kristian" == Kristian Nielsen <knielsen(a)knielsen-hq.org> writes: Kristian> Sergey Petrunya <psergey(a)askmonty.org> writes: >> I've worked through the list and filed >> >> MWL#39 Replication tasks >> >> and its subordinate tasks: >> >> MWL#36 Add a mysqlbinlog option to change the used database >> MWL#37 Add an option to mysqlbinlog to produce SQL script with fewer roundtrips >> MWL#38 Make mysqlbinlog not to output unneeded statements when using --database >> MWL#40 Add a mysqlbinlog option to filter updates to certain tables >> MWL#41 Add a mysqlbinlog option to filter certain kinds of statements Kristian> Thanks, Sergey! I've started to work my way through them and the many Kristian> associated issues to understand for this. Kristian> One idea that occured to me and that I would like to bounce off of you others Kristian> (while I still continue thinking more about it and also working on the Kristian> original proposals): Kristian> In some sense the root of the problem is the magic "BINLOG" statement, which Kristian> really is not very nice. It is much much harder than it should be to see from Kristian> the binlog what data is actually changed from row-based events. Kristian> If the BINLOG statement was using proper syntax showing the actual data Kristian> changes, then the original customer problem would likely be solved as they Kristian> could treat it the same way as statement-based replication events. This is Kristian> especially nice when one considers that even row-based replication uses lots Kristian> of statement-based events, not to mention mixed-mode replication. Kristian> But readable BINLOG statements would be very nice in any case, and solve a Kristian> much more general problem than these worklogs, in an arguably nicer way. Note that it would also be very nice to have in the binlog the exact original statement: - Easier to understand why updates happened. - Would make it easier to find out where in application things went wrong (as you can search for exact strings) - Allow one to filter things based on comments in the statement. The cost would be to have an approximately 2 as big binlog. (Especially insert of big blob's would be a bit painful). Kristian> There are also a number of potential problems that need careful consideration Kristian> of course. I haven't yet fully thought things through, just wanted to throw up Kristian> the idea. Kristian> I went throught the code for RBR events, and came up with the following Kristian> possible syntax: Kristian> BINLOG Kristian> WITH TIMESTAMP xxx SERVER_ID 1 MASTER_POS 415 FLAGS 0x0 Kristian> TABLE db1.table1 AS 1 COLUMNS (INT NOT NULL, BLOB, VARCHAR(100)) FLAGS 0x0 Kristian> TABLE db2.table2 AS 2 COLUMNS (CHAR(10)) FLAGS 0x0 Kristian> WRITE_ROW INTO db1.table1(1,3) VALUES (42, 'foobar'), (10, NULL) FLAGS 0x2 Kristian> UPDATE_ROW INTO db2.table2 (1) (1) VALUES FROM ('beforeval') TO ('toval'), Kristian> FROM ('a') TO ('b') FLAGS 0x0 Kristian> DELETE_ROW INTO db2.table2 (1) VALUES ('row_to_delete') FLAGS 0x0; Kristian> This is basically a dump of what is stored in the events, and would be an Kristian> alternative to BINLOG 'gwWEShMBAA...'. Kristian> So what do people think? The above would be a much better option than using the current syntax. Kristian> The implementation of this is not necessarily all that much harder than the Kristian> suggested worklogs under MWL#39 I think. The server upon reading this would Kristian> just reconstruct the binary representation of the binlog and proceed as the Kristian> old BINLOG statement. The mysqlbinlog program would just print out the Kristian> fields. The main complications are the addition of syntax to the Bison grammer Kristian> plus the need to handle all the possible types. Kristian> If we choose the easiest option in all the MWL#39 subtasks that would probably Kristian> be somewhat easier. On the other hand this would be a much more generally Kristian> useful feature, and would make trivial a lot of the suggested modifications to Kristian> mysqlbinlog. Which of the original customer problems would the above solve ? For exampling, doing general rename of databases wouldn't be much easier to do with the the above syntax (as we still need to handle SBR). Kristian> I'm pretty sure this would be easier than some of the harder options in the Kristian> MWL#39 subtasks. Which one are you thinking about ? (I like the proposed syntax, but don't grasp why things would be simple when doing this ). Kristian> So I need to think a bit more about this to make up my mind if I like it. But Kristian> I think at least it is a very interesting idea. Kristian> Comments? Kristian> (Also, isn't it time to move the discussion to the public Kristian> maria-developers(a)lists.launchpad.net list?) Done. Regards, Monty

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[Maria-developers] Updated (by Psergey): mysqlbinlog: remove undesired effects of format description binlog statement (50)
by worklog-noreply＠askmonty.org 17 Aug '09

17 Aug '09

----------------------------------------------------------------------- WORKLOG TASK -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- TASK...........: mysqlbinlog: remove undesired effects of format description binlog statement CREATION DATE..: Mon, 17 Aug 2009, 14:12 SUPERVISOR.....: Monty IMPLEMENTOR....: COPIES TO......: CATEGORY.......: Server-RawIdeaBin TASK ID........: 50 (http://askmonty.org/worklog/?tid=50) VERSION........: Server-9.x STATUS.........: Un-Assigned PRIORITY.......: 60 WORKED HOURS...: 0 ESTIMATE.......: 0 (hours remain) ORIG. ESTIMATE.: 0 PROGRESS NOTES: -=-=(Psergey - Mon, 17 Aug 2009, 14:13)=-=- High-Level Specification modified. --- /tmp/wklog.50.old.11389 2009-08-17 14:13:05.000000000 +0300 +++ /tmp/wklog.50.new.11389 2009-08-17 14:13:05.000000000 +0300 @@ -1 +1,14 @@ +First item +---------- +AFAIU what needs to be done is: +1. record a source server version (it is in the first binlog event). +2. don't emit a BINLOG statement if the recorded version number is 5.0.x or + below. + +and we'll get a 5.0-applicable binlog. + +Second item +----------- +One question that one needs to sort out before disabling server_id change is +why it was put there in the first place? Should it be always removed? DESCRIPTION: According to complaints in BUG#46640: 1. mysqlbinlog will emit a 5.0-incompatible "format description binlog statement" even when reading a binary log that was produced by 5.0. This will cause an error when one tires to apply mysqlbinlog output to a 5.0.x server. 2. When one applies "format description binlog statement" at the slave, it will change the slave's server_id when applied. This WL is to fix these issues. HIGH-LEVEL SPECIFICATION: First item ---------- AFAIU what needs to be done is: 1. record a source server version (it is in the first binlog event). 2. don't emit a BINLOG statement if the recorded version number is 5.0.x or below. and we'll get a 5.0-applicable binlog. Second item ----------- One question that one needs to sort out before disabling server_id change is why it was put there in the first place? Should it be always removed? ESTIMATED WORK TIME ESTIMATED COMPLETION DATE ----------------------------------------------------------------------- WorkLog (v3.5.9)

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[Maria-developers] Updated (by Psergey): mysqlbinlog: remove undesired effects of format description binlog statement (50)
by worklog-noreply＠askmonty.org 17 Aug '09

17 Aug '09

----------------------------------------------------------------------- WORKLOG TASK -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- TASK...........: mysqlbinlog: remove undesired effects of format description binlog statement CREATION DATE..: Mon, 17 Aug 2009, 14:12 SUPERVISOR.....: Monty IMPLEMENTOR....: COPIES TO......: CATEGORY.......: Server-RawIdeaBin TASK ID........: 50 (http://askmonty.org/worklog/?tid=50) VERSION........: Server-9.x STATUS.........: Un-Assigned PRIORITY.......: 60 WORKED HOURS...: 0 ESTIMATE.......: 0 (hours remain) ORIG. ESTIMATE.: 0 PROGRESS NOTES: -=-=(Psergey - Mon, 17 Aug 2009, 14:13)=-=- High-Level Specification modified. --- /tmp/wklog.50.old.11389 2009-08-17 14:13:05.000000000 +0300 +++ /tmp/wklog.50.new.11389 2009-08-17 14:13:05.000000000 +0300 @@ -1 +1,14 @@ +First item +---------- +AFAIU what needs to be done is: +1. record a source server version (it is in the first binlog event). +2. don't emit a BINLOG statement if the recorded version number is 5.0.x or + below. + +and we'll get a 5.0-applicable binlog. + +Second item +----------- +One question that one needs to sort out before disabling server_id change is +why it was put there in the first place? Should it be always removed? DESCRIPTION: According to complaints in BUG#46640: 1. mysqlbinlog will emit a 5.0-incompatible "format description binlog statement" even when reading a binary log that was produced by 5.0. This will cause an error when one tires to apply mysqlbinlog output to a 5.0.x server. 2. When one applies "format description binlog statement" at the slave, it will change the slave's server_id when applied. This WL is to fix these issues. HIGH-LEVEL SPECIFICATION: First item ---------- AFAIU what needs to be done is: 1. record a source server version (it is in the first binlog event). 2. don't emit a BINLOG statement if the recorded version number is 5.0.x or below. and we'll get a 5.0-applicable binlog. Second item ----------- One question that one needs to sort out before disabling server_id change is why it was put there in the first place? Should it be always removed? ESTIMATED WORK TIME ESTIMATED COMPLETION DATE ----------------------------------------------------------------------- WorkLog (v3.5.9)

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[Maria-developers] New (by Psergey): mysqlbinlog: remove undesired effects of format description binlog statement (50)
by worklog-noreply＠askmonty.org 17 Aug '09

17 Aug '09

----------------------------------------------------------------------- WORKLOG TASK -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- TASK...........: mysqlbinlog: remove undesired effects of format description binlog statement CREATION DATE..: Mon, 17 Aug 2009, 14:12 SUPERVISOR.....: Monty IMPLEMENTOR....: COPIES TO......: CATEGORY.......: Server-RawIdeaBin TASK ID........: 50 (http://askmonty.org/worklog/?tid=50) VERSION........: Server-9.x STATUS.........: Un-Assigned PRIORITY.......: 60 WORKED HOURS...: 0 ESTIMATE.......: 0 (hours remain) ORIG. ESTIMATE.: 0 PROGRESS NOTES: DESCRIPTION: According to complaints in BUG#46640: 1. mysqlbinlog will emit a 5.0-incompatible "format description binlog statement" even when reading a binary log that was produced by 5.0. This will cause an error when one tires to apply mysqlbinlog output to a 5.0.x server. 2. When one applies "format description binlog statement" at the slave, it will change the slave's server_id when applied. This WL is to fix these issues. ESTIMATED WORK TIME ESTIMATED COMPLETION DATE ----------------------------------------------------------------------- WorkLog (v3.5.9)

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[Maria-developers] New (by Psergey): mysqlbinlog: remove undesired effects of format description binlog statement (50)
by worklog-noreply＠askmonty.org 17 Aug '09

17 Aug '09

----------------------------------------------------------------------- WORKLOG TASK -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- TASK...........: mysqlbinlog: remove undesired effects of format description binlog statement CREATION DATE..: Mon, 17 Aug 2009, 14:12 SUPERVISOR.....: Monty IMPLEMENTOR....: COPIES TO......: CATEGORY.......: Server-RawIdeaBin TASK ID........: 50 (http://askmonty.org/worklog/?tid=50) VERSION........: Server-9.x STATUS.........: Un-Assigned PRIORITY.......: 60 WORKED HOURS...: 0 ESTIMATE.......: 0 (hours remain) ORIG. ESTIMATE.: 0 PROGRESS NOTES: DESCRIPTION: According to complaints in BUG#46640: 1. mysqlbinlog will emit a 5.0-incompatible "format description binlog statement" even when reading a binary log that was produced by 5.0. This will cause an error when one tires to apply mysqlbinlog output to a 5.0.x server. 2. When one applies "format description binlog statement" at the slave, it will change the slave's server_id when applied. This WL is to fix these issues. ESTIMATED WORK TIME ESTIMATED COMPLETION DATE ----------------------------------------------------------------------- WorkLog (v3.5.9)

1 0

[Maria-developers] Updated (by Psergey): Add a mysqlbinlog option to produce succint output (45)
by worklog-noreply＠askmonty.org 17 Aug '09

17 Aug '09

----------------------------------------------------------------------- WORKLOG TASK -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- TASK...........: Add a mysqlbinlog option to produce succint output CREATION DATE..: Sat, 15 Aug 2009, 23:40 SUPERVISOR.....: Monty IMPLEMENTOR....: COPIES TO......: CATEGORY.......: Server-RawIdeaBin TASK ID........: 45 (http://askmonty.org/worklog/?tid=45) VERSION........: Server-9.x STATUS.........: Un-Assigned PRIORITY.......: 60 WORKED HOURS...: 0 ESTIMATE.......: 0 (hours remain) ORIG. ESTIMATE.: 0 PROGRESS NOTES: -=-=(Psergey - Mon, 17 Aug 2009, 13:58)=-=- High Level Description modified. --- /tmp/wklog.45.old.10768 2009-08-17 13:58:07.000000000 +0300 +++ /tmp/wklog.45.new.10768 2009-08-17 13:58:07.000000000 +0300 @@ -4,3 +4,5 @@ This will be different from --short-form option. That option causes mysqlbinlog not to print RBR events, i.e. the output is not supposed to be applied. +There is also option to have --short-form do what this WL requires, see MySQL +BUG#18337. -=-=(Guest - Mon, 17 Aug 2009, 11:17)=-=- Dependency created: 39 now depends on 45 -=-=(Guest - Mon, 17 Aug 2009, 11:17)=-=- Dependency deleted: 39 no longer depends on 45 -=-=(Psergey - Sun, 16 Aug 2009, 00:02)=-=- Dependency created: 39 now depends on 45 -=-=(Psergey - Sat, 15 Aug 2009, 23:40)=-=- Title modified. --- /tmp/wklog.45.old.17603 2009-08-15 23:40:38.000000000 +0300 +++ /tmp/wklog.45.new.17603 2009-08-15 23:40:38.000000000 +0300 @@ -1 +1 @@ -Add a mysqlbinlog option to produce siccint output +Add a mysqlbinlog option to produce succint output DESCRIPTION: Add a mysqlbinlog option to produce the most succinct output, without any comments or other statements that are not needed to apply binlog correctly. This will be different from --short-form option. That option causes mysqlbinlog not to print RBR events, i.e. the output is not supposed to be applied. There is also option to have --short-form do what this WL requires, see MySQL BUG#18337. ESTIMATED WORK TIME ESTIMATED COMPLETION DATE ----------------------------------------------------------------------- WorkLog (v3.5.9)

1 0

[Maria-developers] Updated (by Psergey): Add a mysqlbinlog option to produce succint output (45)
by worklog-noreply＠askmonty.org 17 Aug '09

17 Aug '09

----------------------------------------------------------------------- WORKLOG TASK -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- TASK...........: Add a mysqlbinlog option to produce succint output CREATION DATE..: Sat, 15 Aug 2009, 23:40 SUPERVISOR.....: Monty IMPLEMENTOR....: COPIES TO......: CATEGORY.......: Server-RawIdeaBin TASK ID........: 45 (http://askmonty.org/worklog/?tid=45) VERSION........: Server-9.x STATUS.........: Un-Assigned PRIORITY.......: 60 WORKED HOURS...: 0 ESTIMATE.......: 0 (hours remain) ORIG. ESTIMATE.: 0 PROGRESS NOTES: -=-=(Psergey - Mon, 17 Aug 2009, 13:58)=-=- High Level Description modified. --- /tmp/wklog.45.old.10768 2009-08-17 13:58:07.000000000 +0300 +++ /tmp/wklog.45.new.10768 2009-08-17 13:58:07.000000000 +0300 @@ -4,3 +4,5 @@ This will be different from --short-form option. That option causes mysqlbinlog not to print RBR events, i.e. the output is not supposed to be applied. +There is also option to have --short-form do what this WL requires, see MySQL +BUG#18337. -=-=(Guest - Mon, 17 Aug 2009, 11:17)=-=- Dependency created: 39 now depends on 45 -=-=(Guest - Mon, 17 Aug 2009, 11:17)=-=- Dependency deleted: 39 no longer depends on 45 -=-=(Psergey - Sun, 16 Aug 2009, 00:02)=-=- Dependency created: 39 now depends on 45 -=-=(Psergey - Sat, 15 Aug 2009, 23:40)=-=- Title modified. --- /tmp/wklog.45.old.17603 2009-08-15 23:40:38.000000000 +0300 +++ /tmp/wklog.45.new.17603 2009-08-15 23:40:38.000000000 +0300 @@ -1 +1 @@ -Add a mysqlbinlog option to produce siccint output +Add a mysqlbinlog option to produce succint output DESCRIPTION: Add a mysqlbinlog option to produce the most succinct output, without any comments or other statements that are not needed to apply binlog correctly. This will be different from --short-form option. That option causes mysqlbinlog not to print RBR events, i.e. the output is not supposed to be applied. There is also option to have --short-form do what this WL requires, see MySQL BUG#18337. ESTIMATED WORK TIME ESTIMATED COMPLETION DATE ----------------------------------------------------------------------- WorkLog (v3.5.9)

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[Maria-developers] Updated (by Knielsen): Add a mysqlbinlog option to filter certain kinds of statements (41)
by worklog-noreply＠askmonty.org 17 Aug '09

17 Aug '09

----------------------------------------------------------------------- WORKLOG TASK -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- TASK...........: Add a mysqlbinlog option to filter certain kinds of statements CREATION DATE..: Mon, 10 Aug 2009, 15:30 SUPERVISOR.....: Monty IMPLEMENTOR....: COPIES TO......: CATEGORY.......: Client-BackLog TASK ID........: 41 (http://askmonty.org/worklog/?tid=41) VERSION........: Benchmarks-3.0 STATUS.........: Un-Assigned PRIORITY.......: 60 WORKED HOURS...: 0 ESTIMATE.......: 0 (hours remain) ORIG. ESTIMATE.: 0 PROGRESS NOTES: -=-=(Knielsen - Mon, 17 Aug 2009, 13:56)=-=- High-Level Specification modified. --- /tmp/wklog.41.old.10632 2009-08-17 13:56:52.000000000 +0300 +++ /tmp/wklog.41.new.10632 2009-08-17 13:56:52.000000000 +0300 @@ -14,3 +14,10 @@ - Remove all pre-space - Compare the string case-insensitively - etc + +Option 3: + +Server-side support for ignoring certain statements: + + SET SESSION ignored_statements="alter table, analyze table, ..."; + -=-=(Knielsen - Fri, 14 Aug 2009, 14:17)=-=- High-Level Specification modified. --- /tmp/wklog.41.old.6963 2009-08-14 14:17:32.000000000 +0300 +++ /tmp/wklog.41.new.6963 2009-08-14 14:17:32.000000000 +0300 @@ -1,6 +1,11 @@ The implementation will depend on design choices made in WL#40: -- If we decide to parse the statement, SQL-verb filtering will be trivial -- If we decide not to parse the statement, we still can reliably distinguish the + +Option 1: + +If we decide to parse the statement, SQL-verb filtering will be trivial + +Option 2: +If we decide not to parse the statement, we still can reliably distinguish the statement by matching the first characters against a set of patterns. If we chose the second, we'll have to perform certain normalization before -=-=(Psergey - Mon, 10 Aug 2009, 15:47)=-=- High-Level Specification modified. --- /tmp/wklog.41.old.13282 2009-08-10 15:47:13.000000000 +0300 +++ /tmp/wklog.41.new.13282 2009-08-10 15:47:13.000000000 +0300 @@ -2,3 +2,10 @@ - If we decide to parse the statement, SQL-verb filtering will be trivial - If we decide not to parse the statement, we still can reliably distinguish the statement by matching the first characters against a set of patterns. + +If we chose the second, we'll have to perform certain normalization before +matching the patterns: + - Remove all comments from the command + - Remove all pre-space + - Compare the string case-insensitively + - etc -=-=(Psergey - Mon, 10 Aug 2009, 15:35)=-=- High-Level Specification modified. --- /tmp/wklog.41.old.12689 2009-08-10 15:35:04.000000000 +0300 +++ /tmp/wklog.41.new.12689 2009-08-10 15:35:04.000000000 +0300 @@ -1 +1,4 @@ - +The implementation will depend on design choices made in WL#40: +- If we decide to parse the statement, SQL-verb filtering will be trivial +- If we decide not to parse the statement, we still can reliably distinguish the +statement by matching the first characters against a set of patterns. -=-=(Psergey - Mon, 10 Aug 2009, 15:31)=-=- Dependency created: 39 now depends on 41 DESCRIPTION: Add a mysqlbinlog option to filter certain kinds of statements, i.e. (syntax subject to discussion): mysqlbinlog --exclude='alter table,drop table,alter database,...' HIGH-LEVEL SPECIFICATION: The implementation will depend on design choices made in WL#40: Option 1: If we decide to parse the statement, SQL-verb filtering will be trivial Option 2: If we decide not to parse the statement, we still can reliably distinguish the statement by matching the first characters against a set of patterns. If we chose the second, we'll have to perform certain normalization before matching the patterns: - Remove all comments from the command - Remove all pre-space - Compare the string case-insensitively - etc Option 3: Server-side support for ignoring certain statements: SET SESSION ignored_statements="alter table, analyze table, ..."; ESTIMATED WORK TIME ESTIMATED COMPLETION DATE ----------------------------------------------------------------------- WorkLog (v3.5.9)

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[Maria-developers] Updated (by Knielsen): Add a mysqlbinlog option to filter certain kinds of statements (41)
by worklog-noreply＠askmonty.org 17 Aug '09

17 Aug '09

----------------------------------------------------------------------- WORKLOG TASK -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- TASK...........: Add a mysqlbinlog option to filter certain kinds of statements CREATION DATE..: Mon, 10 Aug 2009, 15:30 SUPERVISOR.....: Monty IMPLEMENTOR....: COPIES TO......: CATEGORY.......: Client-BackLog TASK ID........: 41 (http://askmonty.org/worklog/?tid=41) VERSION........: Benchmarks-3.0 STATUS.........: Un-Assigned PRIORITY.......: 60 WORKED HOURS...: 0 ESTIMATE.......: 0 (hours remain) ORIG. ESTIMATE.: 0 PROGRESS NOTES: -=-=(Knielsen - Mon, 17 Aug 2009, 13:56)=-=- High-Level Specification modified. --- /tmp/wklog.41.old.10632 2009-08-17 13:56:52.000000000 +0300 +++ /tmp/wklog.41.new.10632 2009-08-17 13:56:52.000000000 +0300 @@ -14,3 +14,10 @@ - Remove all pre-space - Compare the string case-insensitively - etc + +Option 3: + +Server-side support for ignoring certain statements: + + SET SESSION ignored_statements="alter table, analyze table, ..."; + -=-=(Knielsen - Fri, 14 Aug 2009, 14:17)=-=- High-Level Specification modified. --- /tmp/wklog.41.old.6963 2009-08-14 14:17:32.000000000 +0300 +++ /tmp/wklog.41.new.6963 2009-08-14 14:17:32.000000000 +0300 @@ -1,6 +1,11 @@ The implementation will depend on design choices made in WL#40: -- If we decide to parse the statement, SQL-verb filtering will be trivial -- If we decide not to parse the statement, we still can reliably distinguish the + +Option 1: + +If we decide to parse the statement, SQL-verb filtering will be trivial + +Option 2: +If we decide not to parse the statement, we still can reliably distinguish the statement by matching the first characters against a set of patterns. If we chose the second, we'll have to perform certain normalization before -=-=(Psergey - Mon, 10 Aug 2009, 15:47)=-=- High-Level Specification modified. --- /tmp/wklog.41.old.13282 2009-08-10 15:47:13.000000000 +0300 +++ /tmp/wklog.41.new.13282 2009-08-10 15:47:13.000000000 +0300 @@ -2,3 +2,10 @@ - If we decide to parse the statement, SQL-verb filtering will be trivial - If we decide not to parse the statement, we still can reliably distinguish the statement by matching the first characters against a set of patterns. + +If we chose the second, we'll have to perform certain normalization before +matching the patterns: + - Remove all comments from the command + - Remove all pre-space + - Compare the string case-insensitively + - etc -=-=(Psergey - Mon, 10 Aug 2009, 15:35)=-=- High-Level Specification modified. --- /tmp/wklog.41.old.12689 2009-08-10 15:35:04.000000000 +0300 +++ /tmp/wklog.41.new.12689 2009-08-10 15:35:04.000000000 +0300 @@ -1 +1,4 @@ - +The implementation will depend on design choices made in WL#40: +- If we decide to parse the statement, SQL-verb filtering will be trivial +- If we decide not to parse the statement, we still can reliably distinguish the +statement by matching the first characters against a set of patterns. -=-=(Psergey - Mon, 10 Aug 2009, 15:31)=-=- Dependency created: 39 now depends on 41 DESCRIPTION: Add a mysqlbinlog option to filter certain kinds of statements, i.e. (syntax subject to discussion): mysqlbinlog --exclude='alter table,drop table,alter database,...' HIGH-LEVEL SPECIFICATION: The implementation will depend on design choices made in WL#40: Option 1: If we decide to parse the statement, SQL-verb filtering will be trivial Option 2: If we decide not to parse the statement, we still can reliably distinguish the statement by matching the first characters against a set of patterns. If we chose the second, we'll have to perform certain normalization before matching the patterns: - Remove all comments from the command - Remove all pre-space - Compare the string case-insensitively - etc Option 3: Server-side support for ignoring certain statements: SET SESSION ignored_statements="alter table, analyze table, ..."; ESTIMATED WORK TIME ESTIMATED COMPLETION DATE ----------------------------------------------------------------------- WorkLog (v3.5.9)

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[Maria-developers] Updated (by Knielsen): Add a mysqlbinlog option to change the used database (36)
by worklog-noreply＠askmonty.org 17 Aug '09

17 Aug '09

----------------------------------------------------------------------- WORKLOG TASK -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- TASK...........: Add a mysqlbinlog option to change the used database CREATION DATE..: Fri, 07 Aug 2009, 14:57 SUPERVISOR.....: Monty IMPLEMENTOR....: COPIES TO......: CATEGORY.......: Server-RawIdeaBin TASK ID........: 36 (http://askmonty.org/worklog/?tid=36) VERSION........: Server-9.x STATUS.........: Un-Assigned PRIORITY.......: 60 WORKED HOURS...: 0 ESTIMATE.......: 0 (hours remain) ORIG. ESTIMATE.: 0 PROGRESS NOTES: -=-=(Knielsen - Mon, 17 Aug 2009, 12:44)=-=- High-Level Specification modified. --- /tmp/wklog.36.old.7834 2009-08-17 12:44:17.000000000 +0300 +++ /tmp/wklog.36.new.7834 2009-08-17 12:44:17.000000000 +0300 @@ -13,7 +13,9 @@ statement refers to tables in current database, so that changing the current database will make the statement to work on a table in a different database). -See also MySQL BUG#42941. +See also MySQL BUG#42941. Note this bug is fixed in MySQL 5.1.37, which is not +merged into MariaDB at the time of writing, but planned to be merged before +release. What we could do ---------------- -=-=(Guest - Sun, 16 Aug 2009, 17:11)=-=- High-Level Specification modified. --- /tmp/wklog.36.old.27162 2009-08-16 17:11:12.000000000 +0300 +++ /tmp/wklog.36.new.27162 2009-08-16 17:11:12.000000000 +0300 @@ -13,6 +13,8 @@ statement refers to tables in current database, so that changing the current database will make the statement to work on a table in a different database). +See also MySQL BUG#42941. + What we could do ---------------- -=-=(Psergey - Mon, 10 Aug 2009, 15:41)=-=- High-Level Specification modified. --- /tmp/wklog.36.old.13035 2009-08-10 15:41:51.000000000 +0300 +++ /tmp/wklog.36.new.13035 2009-08-10 15:41:51.000000000 +0300 @@ -1,5 +1,7 @@ Context ------- +(See http://askmonty.org/wiki/index.php/Scratch/ReplicationOptions for global +overview) At the moment, the server has a replication slave option --replicate-rewrite-db="from->to" -=-=(Guest - Mon, 10 Aug 2009, 11:12)=-=- High-Level Specification modified. --- /tmp/wklog.36.old.6580 2009-08-10 11:12:36.000000000 +0300 +++ /tmp/wklog.36.new.6580 2009-08-10 11:12:36.000000000 +0300 @@ -1,4 +1,3 @@ - Context ------- At the moment, the server has a replication slave option @@ -67,6 +66,6 @@ It will be possible to do the rewrites either on the slave ( --replicate-rewrite-db will work for all kinds of statements), or in -mysqlbinlog (adding a comment is easy and doesn't require use to parse the -statement). +mysqlbinlog (adding a comment is easy and doesn't require mysqlbinlog to +parse the statement). -=-=(Psergey - Sun, 09 Aug 2009, 23:53)=-=- High-Level Specification modified. --- /tmp/wklog.36.old.13425 2009-08-09 23:53:54.000000000 +0300 +++ /tmp/wklog.36.new.13425 2009-08-09 23:53:54.000000000 +0300 @@ -1 +1,72 @@ +Context +------- +At the moment, the server has a replication slave option + + --replicate-rewrite-db="from->to" + +the option affects +- Table_map_log_event (all RBR events) +- Load_log_event (LOAD DATA) +- Query_log_event (SBR-based updates, with the usual assumption that the + statement refers to tables in current database, so that changing the current + database will make the statement to work on a table in a different database). + +What we could do +---------------- + +Option1: make mysqlbinlog accept --replicate-rewrite-db option +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +Make mysqlbinlog accept --replicate-rewrite-db options and process them to the +same extent as replication slave would process --replicate-rewrite-db option. + + +Option2: Add database-agnostic RBR events and --strip-db option +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +Right now RBR events require a databasename. It is not possible to have RBR +event stream that won't mention which database the events are for. When I +tried to use debugger and specify empty database name, attempt to apply the +binlog resulted in this error: + +090809 17:38:44 [ERROR] Slave SQL: Error 'Table '.tablename' doesn't exist' on +opening tables, + +We could do as follows: +- Make the server interpret empty database name in RBR event (i.e. in a + Table_map_log_event) as "use current database". Binlog slave thread + probably should not allow such events as it doesn't have a natural current + database. +- Add a mysqlbinlog --strip-db option that would + = not produce any "USE dbname" statements + = change databasename for all RBR events to be empty + +That way, mysqlbinlog output will be database-agnostic and apply to the +current database. +(this will have the usual limitations that we assume that all statements in +the binlog refer to the current database). + +Option3: Enhance database rewrite +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +If there is a need to support database change for statements that use +dbname.tablename notation and are replicated as statements (i.e. are DDL +statements and/or DML statements that are binlogged as statements), +then that could be supported as follows: + +- Make the server's parser recognize special form of comments + + /* !database-alias(oldname,newname) */ + + and save the mapping somewhere + +- Put the hooks in table open and name resolution code to use the saved + mapping. + + +Once we've done the above, it will be easy to perform a complete, +no-compromise or restrictions database name change in binary log. + +It will be possible to do the rewrites either on the slave ( +--replicate-rewrite-db will work for all kinds of statements), or in +mysqlbinlog (adding a comment is easy and doesn't require use to parse the +statement). + -=-=(Psergey - Sun, 09 Aug 2009, 12:27)=-=- Dependency created: 39 now depends on 36 -=-=(Psergey - Fri, 07 Aug 2009, 14:57)=-=- Title modified. --- /tmp/wklog.36.old.14687 2009-08-07 14:57:49.000000000 +0300 +++ /tmp/wklog.36.new.14687 2009-08-07 14:57:49.000000000 +0300 @@ -1 +1 @@ -Add a mysqlbinlog option to change the database +Add a mysqlbinlog option to change the used database DESCRIPTION: Sometimes there is a need to take a binary log and apply it to a database with a different name than the original name of the database on binlog producer. If one is using statement-based replication, he can achieve this by grepping out "USE dbname" statements out of the output of mysqlbinlog(*). With row-based replication this is no longer possible, as database name is encoded within the the BINLOG '....' statement. This task is about adding an option to mysqlbinlog that would allow to change the names of used databases in both RBR and SBR events. (*) this implies that all statements refer to tables in the current database, doesn't catch updates made inside stored functions and so forth, but still works for a practially-important subset of cases. HIGH-LEVEL SPECIFICATION: Context ------- (See http://askmonty.org/wiki/index.php/Scratch/ReplicationOptions for global overview) At the moment, the server has a replication slave option --replicate-rewrite-db="from->to" the option affects - Table_map_log_event (all RBR events) - Load_log_event (LOAD DATA) - Query_log_event (SBR-based updates, with the usual assumption that the statement refers to tables in current database, so that changing the current database will make the statement to work on a table in a different database). See also MySQL BUG#42941. Note this bug is fixed in MySQL 5.1.37, which is not merged into MariaDB at the time of writing, but planned to be merged before release. What we could do ---------------- Option1: make mysqlbinlog accept --replicate-rewrite-db option ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Make mysqlbinlog accept --replicate-rewrite-db options and process them to the same extent as replication slave would process --replicate-rewrite-db option. Option2: Add database-agnostic RBR events and --strip-db option ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Right now RBR events require a databasename. It is not possible to have RBR event stream that won't mention which database the events are for. When I tried to use debugger and specify empty database name, attempt to apply the binlog resulted in this error: 090809 17:38:44 [ERROR] Slave SQL: Error 'Table '.tablename' doesn't exist' on opening tables, We could do as follows: - Make the server interpret empty database name in RBR event (i.e. in a Table_map_log_event) as "use current database". Binlog slave thread probably should not allow such events as it doesn't have a natural current database. - Add a mysqlbinlog --strip-db option that would = not produce any "USE dbname" statements = change databasename for all RBR events to be empty That way, mysqlbinlog output will be database-agnostic and apply to the current database. (this will have the usual limitations that we assume that all statements in the binlog refer to the current database). Option3: Enhance database rewrite ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ If there is a need to support database change for statements that use dbname.tablename notation and are replicated as statements (i.e. are DDL statements and/or DML statements that are binlogged as statements), then that could be supported as follows: - Make the server's parser recognize special form of comments /* !database-alias(oldname,newname) */ and save the mapping somewhere - Put the hooks in table open and name resolution code to use the saved mapping. Once we've done the above, it will be easy to perform a complete, no-compromise or restrictions database name change in binary log. It will be possible to do the rewrites either on the slave ( --replicate-rewrite-db will work for all kinds of statements), or in mysqlbinlog (adding a comment is easy and doesn't require mysqlbinlog to parse the statement). ESTIMATED WORK TIME ESTIMATED COMPLETION DATE ----------------------------------------------------------------------- WorkLog (v3.5.9)

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