Run Outer Join Query
I am trying to run following query in mysql.
select a.name, a.record, b.data from A a, B b where a.name*=b.name and b.date='2006-07-28'
How can I do this in mysql? I looked up LEFT JOIN but still can't figure it out.
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Multiple Join Query
I have a database with quite a lot of tables all with foreign keys of each other. One of the tables has a one to many relationship (it being the one) with two tables, but it only uses one of them for any one record. Which one is used depends on a field in the main table. This essentially defines three different types of the same item, which has mostly the same fields, but two of them also require additional, multiple record (hence the one to many) information. So the table has a field 'type' which takes the value 1 (in which case no other table is referenced), 2, (in which case the first other table is used) and 3 (in which the other table is used). What I would ideally like to do is have one SQL query which returns information (from the main table) about any record which applies to the day (as it is part of a calendar system) specified in the query. The problem is that to decide if the record is relivent, the query must look through at most two of the three tables. I doubt that there is a way to specify in an SQL query to join to a table depending on the field of the first, and to join all three and perform the query could produce unexpected results if there were for any reason records in the third which referred to the first table. I could do this with several queries, but it would probably be more efficient to do it by one query. Would I be able to do an outer join on this?
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