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Re: help with query multipole items in column
Posted by: Peter Brawley
Date: January 13, 2022 10:26PM

What version of MySQL are you using?

Columns with multiple values per row break a fundamental relational database rule, atomicity: one value per column. A design that breaks that rule is incompetent, needs to be fixed.

And unfortunately your problem description suggests these are EAV (entity-attribute-value) tables. EAV tables are pigs to query, and if the query is ever made to work, it performs like a pig. So if they're EAV tables, the only suggestion I can make is to transform the tables into ordinary relational tables. If they aren't, then please offer a fuller description of the problem including results of ...

show create table v6z59_sv_apptpro3_requests;
show create table v6z59_sv_apptpro3_udfvalues;

Also, your comma join syntax (...FROM v6z59_sv_apptpro3_requests a, v6z59_sv_apptpro3_udfvalues b...) is outmoded, not recommended. Explicit join syntax is preferable.

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Re: help with query multipole items in column
January 13, 2022 10:26PM


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