MySQL upgrade 4.1 to 5 -- conversion of TEXT to VARCHAR?
Posted on 2007-10-15
We are preparing to upgrade from 4.1 to 5. One thing I am wondering about would be the conversion of some TEXT columns to VARCAHR. We have two of tables each having three columns which are allowed to be up to 2000 characters. In 4.1, because of the limits on the size of VARCHAR, we were forced to put these into TEXT columns. With the much larger limit in 5, we could convert these to VARCHAR.
What are the advantages and disadvantages?
Having the separate files to contain the TEXT columns may have some overhead. On the other hand, putting those potentially large data fields into the main table may also have a performance hit.
These columns are sometimes used for text searches of the following type:
WHERE col LIKE '%string%'