June 19, 2013

Comment: Fixing column encoding mess in MySQL

December 18, 2007 By 32 Comments

… the values from original table corrected using the trick: INSERT INTO tmp SELECT … CONVERT(CONVERT(column USING binary) USING utf8) … FROM table Second you could ALTER… run an update which would decode it once. The corresponding CONVERT()s sequence is somewhat more tricky but I believe that…

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Comment: Fixing column encoding mess in MySQL

April 19, 2010 By 32 Comments

… following statement with something else? > UPDATE table SET column=CONVERT(CONVERT(column USING binary) USING utf8) WHERE id=123; Also, I’m just not able to do this thing on my own. Anyone can help me convert…

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Comment: EXPLAIN EXTENDED can tell you all kinds of interesting things

June 16, 2010 By 7 Comments

…’t use indexes due to conversions of charsets. For example it’ll show something like this: SELECT … where (`b`.`t1`.`a` = convert(`b`.`t2`.`b` using utf8)) Sometimes when tables are temporary or created as result…

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Comment: GROUP_CONCAT useful GROUP BY extension

February 18, 2010 By 49 Comments

thank bosss “@Murz, Jasan ” it work for me.. @Murz, Jasan Alternatively you can use CONVERT(group_concat(myInt) USING utf8)

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Comment: GROUP_CONCAT useful GROUP BY extension

January 27, 2009 By 49 Comments

@Murz, Jasan Alternatively you can use CONVERT(group_concat(myInt) USING utf8)

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Post: On Character Sets and Disappearing Tables

June 21, 2012 By 1 Comment

…; Suppose that we decide that we’ll never have any use for UTF8 in this database at all, and that we want to achieve the best performance possible, so we’re going to convert… indexes aren’t being used in the way we were expecting. Whatever the reason, we decide to convert these columns to be…

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Post: Extended EXPLAIN

July 24, 2006 By 9 Comments

…`.`sbtest`.`id` > 6) and (`test`.`sbtest`.`c` = _utf8‘a’) and (`test`.`sbtest`.`pad` = _utf8‘a’)) 1 row in set (0.00 sec… column list, each column was fully quantified plus MySQL optimizer converted c=”a” and pad=c; to c=”a” and pad… information in the message. We can see query is using , it is converted to using . And there is some in being done. Unfortnuately…

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Post: MySQL Upgrade Webinar Questions Followup

June 28, 2012 By 7 Comments

… to inject MySQL 5.0 in between so it will convert binary log events, as described here yet it does not… character set set to utf8? No. MySQL 5.5 continues to support MyISAM tables, so you can continue use them as needed… previous MySQL versions. Moreover utf8 character set continues to cause significant performance overhead so you should only use it in case you…

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Post: InnoDB Full-text Search in MySQL 5.6: Part 2, The Queries!

March 4, 2013 By 7 Comments

…` ( `value` varchar(18) NOT NULL DEFAULT ” ) ENGINE=MEMORY DEFAULT CHARSET=utf8 The docs tell us that we need to create an…) NOT NULL DEFAULT ” ) ENGINE=InnoDB DEFAULT CHARSET=utf8 But, when we try to use this table, here’s what comes back: mysql… take the MyISAM full-text parser code, convert it to a plugin, and use it for InnoDB FT indexes where you’re…

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Post: Trying Archive Storage Engine

November 12, 2006 By 7 Comments

…NULL Update_time: NULL Check_time: NULL Collation: utf8_general_ci Checksum: NULL Create_options: Comment:…due to incremental compression which Archive engine uses, still it should have done much better…. big surprise as I got this table by converting MyISAM table rather than incremental insertions. I…

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