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→SQL Coding rules
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An other advantage of this rule, is that request benefits of index because we are making a compare of a field with a fixed value. When using datediff, you make an operation on field before comparison, this means database can't use the index on field, resulting on very bad performance compared to solution without the datediff.
An other advantage of this rule, is that request benefits of index because we are making a compare of a field with a fixed value. When using datediff, you make an operation on field before comparison, this means database can't use the index on field, resulting on very bad performance compared to solution without the datediff.
+
+* Use $db->ifsql for SQL IF
+Do not include the IF into your forged SQL request. But use instead $db->ifsql() method to you will make a SQL IF that is compatible with all SQL databases.
== Mysql specificities ==
== Mysql specificities ==