i got a table named date_use
and has a column id
& dateUSE
.
id dateUSE
1 2015-01-01
2 2015-01-01
3 2015-01-01
4 2015-01-02
5 2015-01-02
now if i will submit another date 2015-01-01 to this table using my php code, it will first count the rows that has the same date and if it is equals to 3 then the date 2015-01-01 that i selected will not be saved and will not be available to be selected.
i want to compare first the date i submitted then if that date has already inputted 3 times in the database then the date i submitted will not be available to be saved and i will just select other date.
just like in checking a reservation date availability, i will select a date then click a button then it will check first my database to see if that date was entered three times then the date i selected will not be available.
You should do this:
SELECT
COUNT(*) AS Total
FROM tablenames
WHERE dateUSE = '$date';
Then in your php code, read this value for total
if it is equal 3, then don't do the insert.
You need either a trigger for this or application level logic. Here is an example of application-level logic:
insert into t(date)
select '2015-01-01' as newdate
from (select count(*) as cnt
from t
where date = '2015-01-01'
) x
where x.cnt < 3;
You can try execute this in phpmyadmin if you have installed:
SELECT count(*) FROM date_use WHERE dateUSE='2015-01-02';
after this you will figure out how to implement this in script.
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