pcsoft.us.windevCopyright 2026, PC SOFT1 Jul 2016 17:11:00 Z30 Jun 2016 11:52:00 ZHi, I use 2 files with the same description, one on MySQL and one on HFSQL. I have to update the records of HFSQL file with the records of MySQL file. I use the column tms_umod (timestamp of the last modification) to know which records need to be updated. So I execute this query on HFSQL file: "SELECT tms_umod FROM HFile ORDER BY tms_umod DESC LIMIT 1" dtLastMod is DateTime = HFile.tms_umod And then, I execute this one on MySQL file: "SELECT * FROM MyFile WHERE tms_umod > dtLastMod" And then starts the copy.., The problem for me is the execution of the first query (on HFSQL), it's too slow!! WHY? I've tried to execute the same query on MySQL and it take less than 0,01 seconds Thanks Best regards Dann30WEBDEVen_UShttps://forum.pcsoft.fr/es-ES/pcsoft.us.windev/58396-wd20-execution-query-slow-hfsql-fast-mysql/read.awpmoderateur@pcsoft.fr (El moderador)webmaster@pcsoft.fr (El webmaster)guestpcsoft.us.windevhttps://forum.pcsoft.fr/es-ES/pcsoft.us.windev/58396-wd20-execution-query-slow-hfsql-fast-mysql-58441/read.awp1 Jul 2016 17:11:00 ZHi Dann that does NOT change my answer... I don't know what kind of magic Mysql is using to find a result that fast without a…https://forum.pcsoft.fr/es-ES/pcsoft.us.windev/58396-wd20-execution-query-slow-hfsql-fast-mysql-58441/read.awphttps://forum.pcsoft.fr/es-ES/pcsoft.us.windev/58396-wd20-execution-query-slow-hfsql-fast-mysql-58441/read.awp[WD20] Execution of query slow on HFSQL, fast on MySQLguestpcsoft.us.windevhttps://forum.pcsoft.fr/es-ES/pcsoft.us.windev/58396-wd20-execution-query-slow-hfsql-fast-mysql-58440/read.awp1 Jul 2016 15:10:00 ZHi Fabrice, also in MySQL the column tms_umod is not an index, but the query is so much faster than the same query on HFSQL. …https://forum.pcsoft.fr/es-ES/pcsoft.us.windev/58396-wd20-execution-query-slow-hfsql-fast-mysql-58440/read.awphttps://forum.pcsoft.fr/es-ES/pcsoft.us.windev/58396-wd20-execution-query-slow-hfsql-fast-mysql-58440/read.awp[WD20] Execution of query slow on HFSQL, fast on MySQLguestpcsoft.us.windevhttps://forum.pcsoft.fr/es-ES/pcsoft.us.windev/58396-wd20-execution-query-slow-hfsql-fast-mysql-58439/read.awp1 Jul 2016 14:21:00 ZTry this: SELECT max(tms_umod) FROM HFile asssuming tms_umod was indexed. HTH Kinghttps://forum.pcsoft.fr/es-ES/pcsoft.us.windev/58396-wd20-execution-query-slow-hfsql-fast-mysql-58439/read.awphttps://forum.pcsoft.fr/es-ES/pcsoft.us.windev/58396-wd20-execution-query-slow-hfsql-fast-mysql-58439/read.awp[WD20] Execution of query slow on HFSQL, fast on MySQLguestpcsoft.us.windevhttps://forum.pcsoft.fr/es-ES/pcsoft.us.windev/58396-wd20-execution-query-slow-hfsql-fast-mysql-58436/read.awp1 Jul 2016 14:01:00 ZHi Dann, if you don't have an index on tms_umod, then you have your answer... add one and the result will be MUCH faster..…https://forum.pcsoft.fr/es-ES/pcsoft.us.windev/58396-wd20-execution-query-slow-hfsql-fast-mysql-58436/read.awphttps://forum.pcsoft.fr/es-ES/pcsoft.us.windev/58396-wd20-execution-query-slow-hfsql-fast-mysql-58436/read.awp[WD20] Execution of query slow on HFSQL, fast on MySQLguestpcsoft.us.windevhttps://forum.pcsoft.fr/es-ES/pcsoft.us.windev/58396-wd20-execution-query-slow-hfsql-fast-mysql-58425/read.awp1 Jul 2016 08:51:00 ZHi, @Joris Yes I think that ORDER BY is the statement that makes the query slower. @Fabrice I was talking about the quer…https://forum.pcsoft.fr/es-ES/pcsoft.us.windev/58396-wd20-execution-query-slow-hfsql-fast-mysql-58425/read.awphttps://forum.pcsoft.fr/es-ES/pcsoft.us.windev/58396-wd20-execution-query-slow-hfsql-fast-mysql-58425/read.awp[WD20] Execution of query slow on HFSQL, fast on MySQLguestpcsoft.us.windevhttps://forum.pcsoft.fr/es-ES/pcsoft.us.windev/58396-wd20-execution-query-slow-hfsql-fast-mysql-58415/read.awp1 Jul 2016 01:25:00 ZHi Dann I ditched HFSQL years ago as I found it way slower than MySQL, and certainly far less capable when it comes to more c…https://forum.pcsoft.fr/es-ES/pcsoft.us.windev/58396-wd20-execution-query-slow-hfsql-fast-mysql-58415/read.awphttps://forum.pcsoft.fr/es-ES/pcsoft.us.windev/58396-wd20-execution-query-slow-hfsql-fast-mysql-58415/read.awp[WD20] Execution of query slow on HFSQL, fast on MySQLguestpcsoft.us.windevhttps://forum.pcsoft.fr/es-ES/pcsoft.us.windev/58396-wd20-execution-query-slow-hfsql-fast-mysql-58404/read.awp30 Jun 2016 16:46:00 ZHi what is TOO SLOW? Is there an index on the timestamp ? How is the HFSQL setup (computer, drive, ram, cache= Why not do …https://forum.pcsoft.fr/es-ES/pcsoft.us.windev/58396-wd20-execution-query-slow-hfsql-fast-mysql-58404/read.awphttps://forum.pcsoft.fr/es-ES/pcsoft.us.windev/58396-wd20-execution-query-slow-hfsql-fast-mysql-58404/read.awp[WD20] Execution of query slow on HFSQL, fast on MySQLguestpcsoft.us.windevhttps://forum.pcsoft.fr/es-ES/pcsoft.us.windev/58396-wd20-execution-query-slow-hfsql-fast-mysql-58402/read.awp30 Jun 2016 16:05:00 ZHi Dann, Does the use of the 'order by' make any difference in speed? Regards, Joris.https://forum.pcsoft.fr/es-ES/pcsoft.us.windev/58396-wd20-execution-query-slow-hfsql-fast-mysql-58402/read.awphttps://forum.pcsoft.fr/es-ES/pcsoft.us.windev/58396-wd20-execution-query-slow-hfsql-fast-mysql-58402/read.awp[WD20] Execution of query slow on HFSQL, fast on MySQL