I want to get distinct records (only one field) from a MySQL table, and that field contain only digits.
Example:
00010000
01111100
01112000
01118000
02301201
But distinct records is considered on base on first 2 digits. So in the case above, I need to get back only 3 records:
00010000
01112000
02301201
More over, I would like to trim the rest of the digits, so the actual end result should be:
00
01
02
So distinct and group by will not cut here. Any idea?
Assuming you wanted the least value from among duplicates, you could try:
SELECT t1.col
FROM yourTable t1
INNER JOIN
(
SELECT LEFT(col, 2) AS prefix, MIN(col) AS min_col
FROM yourTable
GROUP BY LEFT(col, 2)
) t2
ON LEFT(t1.col, 2) = t2.prefix AND
t1.col = t2.min_col;
Note: Numbers in MySQL don't start with zeroes, so your requirement (and this answer) only make sense if your column is text.
DISTINCT
will work fine with LEFT
to give the results you want:
SELECT DISTINCT(LEFT(value, 2)) AS value
FROM data
ORDER BY value
Output
00
01
02
If you only want the trimmed value, try this:
SELECT SUBSTRING(yourColumn,1,2) as trimmedval
FROM Table
GROUP BY SUBSTRING(yourColumn,1,2)
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