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Comments - How to use Join or Union to get the data I need.

3 years, 2 months ago Daniel Black
Re: How to use Join or Union to get the data I need.

I'm having trouble following this without sample data and non-sql logic so I'll try to offer some basic tips:

To get your [ field_id 3 and 4] criteria it depends if you want them on the same row, or different rows.

On the same row you'd used two table aliases of the same table like `FROM dbc_bp_xprofile_data AS f3 JOIN dbc_bp_xprofile_data AS f4 ON f3.field_id=3 AND f4.field_id=4 AND ... `

For separate rows you'd use UNION ALL where each branch uses a different field_id.

SELECT ... FROM db_bp_group_members JOIN (SELECT user_id FROM dbc_bp_xprofile_data WHERE field_id=3 UNION ALL SELECT user_id FROM dbc_bp_xprofile_data WHERE field_id=4)

Or:

SELECT ... FROM db_bp_group_members JOIN dbc_bp_xprofile_data WHERE field_id IN (3,4) ON ...

INSERT ... SELECT can be used with more complicated selects like above.

 
3 years, 2 months ago S G
Re: How to use Join or Union to get the data I need.

Thank you and Apologies - have provided sample data above.....

 
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