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I'm seeing queries in my MySQL slow query log that have the character "N" instead of a specific value. Can I change that? I need in logs the real value with witch the query was executed.

I'm using MySQL 5.5.32.

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which mysql version? what does 'show variables like "%log%"' say? Are your sure the value is not really "N" (perhaps due to bug at application side)? – Matija Nalis Aug 6 '13 at 17:32
No errors, the queries are executed well, mysql slow log is well configured and show the queries with its time values, just that instead of actually value for some parameters are passed by the app, it show N. I' using 5.5.32 and and the output of show variables like "%log%" is: expire_logs_days | 10 Thanks for reply. – gsi-frank Aug 6 '13 at 17:51
Are you using mysqldumpslow to read your slow query log? – Ladadadada Aug 6 '13 at 18:39
Uff, what a stupid mistake :( Days ago I build a command to query the log using mysqldumpslow and pipe the output to less so I can read it, but now while reading data I forget that data don't come from file directly and that mysqldumpslow could be (as actually is) making some kind of change to the queries to summarize it. Thanks a lot @Ladadadada, if you write a answer I will select it. Thanks again for the help! – gsi-frank Aug 6 '13 at 19:00
up vote 1 down vote accepted

Are you using mysqldumpslow to read your slow query log?

mysqldumpslow converts all numbers to N and all strings to 'S'. It also normalises the case of all queries, any whitespace and any quoting before aggregating all similar queries together.

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