I have an Access 2010 pass-through query to a large MySQL 5.2 backend table. The WHERE clause of the query usually has several of the usual operators : =, >,<, like, between, not null, etc.
I notice that the sequence of the operators in the query makes a big difference to the retrieval times. For example, putting a 'like' operator before an 'equals' operator, takes four times as long as the other way round. (All of the relevant fields are indexed.)
The operators are held in a table, and I have it in mind to give them a sequence number, so that VBA constructs the query in the most efficient way
Is there a recognised 'pecking order' for MySQL query operators?
I notice that the sequence of the operators in the query makes a big difference to the retrieval times. For example, putting a 'like' operator before an 'equals' operator, takes four times as long as the other way round. (All of the relevant fields are indexed.)
The operators are held in a table, and I have it in mind to give them a sequence number, so that VBA constructs the query in the most efficient way
Is there a recognised 'pecking order' for MySQL query operators?
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