SELECT QUERY结构

Question

I have a query I am hoping to shorten.

SELECT date1, date2, date3, date4, date5, date6, date7 FROM dates_db 
WHERE date1 =('$date1') OR date1 =('$date2') OR date1=('$date3') 
OR date1=('$date4') OR date1=('$date5') OR date1=('$date6') 
OR date1=('$date7') OR date2 =('$date1') OR date2 =('$date2') 
OR date2=('$date3') OR date2=('$date4') OR date2=('$date5')
OR date2=('$date6') OR date2=('$date7') OR date3 =('$date1') 
OR date3 =('$date2')OR date3=('$date3') OR date3=('$date4') 
OR date3=('$date5') OR date3=('$date6') OR date3=('$date7')

and so on for date 1-7 .

This query is massive, is there any way of shortening it. This is for a calender type design where it is looking for data entries that are in different days. So if a date matches then it will post it to the calendar.

Answer 1

You can use the IN predicate instead of these OR's like so:

SELECT date1, date2, date3, date4, date5, date6, date7
FROM dates_db 
WHERE date1 IN ('$date1','$date2','$date3','$date4','$date5','$date6','$date7')
  OR  date2 IN ('$date1','$date2','$date3','$date4','$date5','$date6','$date7')
  OR  date3 IN ('$date1','$date2','$date3','$date4','$date5','$date6','$date7')
  ...