So I'm fairly new to web development and I haven't really used php and mysql much before.
I was wanting to query my database to find out how many results had the same value for a certain field. I was thinking along the following lines:
SELECT value_a, COUNT(*)
FROM table_a
WHERE value_a = (SELECT DISTINCT value_a FROM table_a)
but obviously I can't have multiple values from my inner query. How could I do something like this?
Simply do -
IF you want to check a single value -
SELECT COUNT(*) value_a_count
FROM table_a
WHERE value_a = 'value_to_check'
GROUP BY value_a
Or for every values -
SELECT value_a, COUNT(*) value_a_count
FROM table_a
GROUP BY value_a
put your result(check_value) in this query
SELECT COUNT(*) count_value
FROM table_a
WHERE value_a IN (check_value)
GROUP BY value_a
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