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Table of Contents
1. General Information
2. MySQL Installation
3. Tutorial Introduction
4. Database Administration
5. MySQL Optimisation
6. MySQL Language Reference
7. MySQL Table Types
8. MySQL APIs
9. Extending MySQL

318 MySQL Technical Reference for Version 4.0.3 Due to the non-transactional nature of MyISAM tables, it is possible to have a query that will only partially update a table and return an error code. This can happen, for example, on a multi-row insert that has one row violating a key constraint, or if a long update query is killed after updating some of the rows. If that happens on the master, the slave thread will exit and wait for the DBA to decide what to do about it unless the error code is legitimate and the query execution results in the same error code. If this error code validation behaviour is not desirable, some ( or all) errors could be masked out with slave-skip-errors option starting in Version 3.23.47. While individual tables can be excluded from replication with replicate-do-table/ ignore-table or replicate-wild-do-table/replicate-wild-ignore-table, there are currently some design deciencies that in some rather rare cases produce unex- pected results. The replication protocol does not inform the slave explicitly which tables are going to be modied by the query { so the slave has to parse the query to know this. To avoid redundant parsing for queries that will end up actually being ex- ecuted, table exclusion is currently implemented by sending the query to the standard MySQL parser, which will short-circuit the query and report success if it detects that the table should be ignored. In addition to several ineciencies, this approach is also more bug prone, and there are two known bugs as of Version 3.23.49 { because the parser automatically opens the table when parsing some queries the ignored table has to exist on the slave. The other bug is that if the ignored table gets partially updated, the slave thread will not notice that the table actually should have been ignored and will suspend the replication process. While the above bugs are conceptually very simple to x, we have not yet found a way to do this without a sigcant code change that would compromize the stability status of 3.23 branch. There exists a workaround for both if in the rare case it happens to aect your application { use slave-skip-errors. 4.10.5 Replication Options in `my.cnf' If you are using replication, we recommend that you use MySQL Version 3.23.30 or later. Older versions work, but they do have some bugs and are missing some features. Some of the options mentioned here may not be available in your version if it is not the most recent one. For all options specic to the 4.0 branch, there is a note indicating so. Otherwise, if you discover that the option you are interested in is not available in your 3.23 version, and you really need it, please upgrade to the most recent 3.23 branch. Please be aware that 4.0 branch is still in alpha, so some things may not be working as smoothly as you would like. If you really would like to try the new features of 4.0, we recommend you do it in such a way that in case there is a problem your mission critical applications will not be disrupted. On both master and slave you need to use the server-id option. This sets an unique replication id. You should pick a unique value in the range between 1 to 2^32-1 for each master and slave. Example: server-id=3 The following table describes the options you can use for the MASTER: Option Description

MySQL Reference Manual

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