… let me clarify what MySQL Query Cache is – I’ve seen number of people being confused, thinking MySQL Query Cache is the… which would need extra care – it is not implemented. Cursors get data in chunks so it is even harder to implement. Might… is good idea to use query cache ? Third party application – You can’t change how it works with MySQL to add caching…
Post: MySQL Prepared Statements
August 2, 2006 By 19 Comments
… be used in textual protocol, which not only consumed time but also required extra memory consumption both on server and client. So in MySQL… prepared statements – Many memory leaks reported in MySQL Server turned out to be prepare statements or cursors which were forgotten to be closed…
Post: 10+ Ways to Crash or Overload MySQL
November 13, 2007 By 20 Comments
… tables in MySQL 5.1 Disk Space For MyISAM tables hosting providers used to use disk quotas for MyISAM tables. You can also use similar… Procedures Cursors – Cursors inside of stored procedures are implemented as temporary tables, so by opening large amount of cursors which are handled as in…
Post: MySQL Server Memory Usage
May 17, 2006 By 18 Comments
… should they estimate memory consumption by MySQL Server in given configuration. What is the formula they could use. The reasons to worry about… lot of memory Prepared statements and Cursors. Single connection may have many prepared statements and cursors. Their number finally can be limited…
Post: MySQL Stored Procedures problems and use practices
June 12, 2007 By 21 Comments
… fan of Stored Procedures, At least not in the form they are currently implemented in MySQL 5.0 Only SQL as a Language… also forces you to use a lot of foreign constructs to “original” MySQL style – to process data via cursors, handle error via Handlers… will log some information in MySQL table but it is not convenient enough. Bad Parser Error Messages MySQL Parser is in general far from…
Comment: MySQL: Data Storage or Data Processing
November 19, 2007 By 9 Comments
… form its cursors, that use row level locks and do not interfere with data load and retrieval. Ideal for background processes. In MySQL cursor syntax is obscure, and I think that many people still are not using them at all.
Comment: MySQL Stored Procedures problems and use practices
September 6, 2010 By 21 Comments
… used to debug code in MySQL: 1. Control execution of stored code on the server (used in dbForge Studio for MySQL ) 2. Interpretation of stored code in… reading a cursor, work with variables) or an error on the server. From release to release, sometimes errors appear in MySQL interpreter, or…
Comment: A micro-benchmark of stored routines in MySQL
August 17, 2009 By 7 Comments
… the population of countries that speak a given language, use a cursor to get the rows for the countries that speak the… | +——————–+ 1 row in set (0.05 sec) mysql> SELECT sql_no_cache sum(ci.Population) FROM City AS ci WHERE CountryCode IN ( SELECT… | +——————–+ 1 row in set (0.06 sec) mysql> SELECT sql_no_cache sum(ci.Population) FROM City AS ci WHERE CountryCode IN ( SELECT…
Post: What does Handler_read_rnd mean?
June 15, 2010 By 15 Comments
MySQL‘s SHOW STATUS command has two counters that are often confusing and result in “what … a cursor operation: read the “next” row in the table. The operation advances the cursor position so…using the position to fetch each one. This is quite likely to result in retrieving rows from random points in…
Comment: INSERT INTO ... SELECT Performance with Innodb tables.
July 21, 2006 By 21 Comments
Though it takes longer, You could also use cursors to avoid the locks. Examples can be found on this URL and in the comments: http://dev.mysql.com/doc/refman/5.0/en/cursors.html
