Using two variables from PHP on the same WHERE in MySQL

I'm trying to extract data from a MySQL server with PHP. The information has a date field like this YYYYMM (fx. 201108). My question is how would an SQL query look if I wanted to return the first or last half of a specific year? I have tired something like this, however the lessthan seems to be ignored:

SELECT * FROM `poster` WHERE mdr开发者_StackOverflow LIKE '2011%' AND mdr < '%06'

I'm afraid google havnt been much help for me.

you can do this, but not with VARCHAR or TEXT:

SELECT * FROM `poster` WHERE mdr < '201106' AND mdr > '201100'

You can only use the % and _ wildcards with the LIKE statement.
This will work, but using any function on a field will kill any opportunity to use indexes, slowing things down.

SELECT * FROM poster WHERE mdr LIKE '2011%' AND right(mdr,2) > '06'

See:
http://dev.mysql.com/doc/refman/5.0/en/string-functions.html

Try th folowing:

SELECT * FROM `poster` WHERE mdr LIKE '2011%' AND MONTH(STR_TO_DATE(mdr, '%Y%m')) < 06

TRY ( assuming that datatype is varchar)

SELECT SUBSTRING('YYYYDDMM',FROM 0 FOR 2) AS firstHalf, 
       SUBSTRING('YYYYDDMM',FROM 2 FOR 2) AS SecondHalf
FROM yourTable

References

• string functions

• datetime functions