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    1. POCorrelated subqueries in MySql - how to evaluate outer query first?
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    1. CO"That is really not the way ..." - Well... I would normally agree to this (and make an extra table as you suggest), especially since that gives you the possibility to add more info than just the column name and column comment. BUT in this case (as name and description is all that is needed) putting them as columns means that i can omit one join and thus speed up normal operation a little bit. With the "better" way I would have to do "usertable JOIN usergroups JOIN usergroupproperties", now "usertable JOIN usergroups" is enough. And.. The boss asked for it! ;-)
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    2. COHmmm... Well I can't argue if the structure is set in stone and unchangeable, but as far as performance goes, you won't get better performance in a relational database by solving it in a non-relational way. Not in this case anyways. Having another table will definitely be faster than dynamic SQL thanks to internal optimizations.
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    3. COHmm... That sounds really strange to me... Are you sure? I men - of course the kind of query we are discussing here will be quite slow, but normally (when not accessing the admin page basically) the only info needed is user + group + group properties (which means a join of two tables, one row from each table). Otherwise the result is has to be joined from three tables (fetching one row from each). Sure, the difference might not be big, but it cant be quicker with 3 tables, right? Also - in the latter case - does foreign keys has to be specified explicitly to get the performance advantage?
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Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

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