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Selecting rows from a table by One a field from other table

开发者 https://www.devze.com 2023-03-09 22:03 出处:网络
What i want, to display rows from a table which is selected by a field from other table single value, lets say to display images from a table by last category id.

What i want, to display rows from a table which is selected by a field from other table single value, lets say to display images from a table by last category id.

I have this type of query, but this return me all matching keys rows, if i inset LIMIT 1 then it return one row...

SELECT i.prof_image FROM profile_images i
JOIN images_cat cat ON (cat.cat_id = i.cat_id)
GROUP BY i.prof_image; 
//OR LIMIT 1;

Any idea to fix this problem. (i.e. d开发者_如何学Cisplaying the latest category images)?


This will work for your specific example.. If you need to be more selective, then please post some more details..

SELECT i.prof_image 
FROM profile_images i 
WHERE cat_id = (select max(cat_id) from images_cat)


SELECT * FROM table_1
LEFT JOIN table_2 ON table_1.id = table_2.id

This query will grab all things in table_2 that have the same id value.

Note that it is a LEFT JOIN - which means that if there are no matching values in table_2, it will still return the values from table_1.

What is your intent with using last()?

Hope this helps.

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