If I alter MySQL table column to increase size, will it delete data in the column?

I have a varchar column that needs more space. How can I increase the size of the column (the number of characters it can have inserted into it), and not lose the data that is in there?

Than开发者_如何学JAVAks!

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It won't delete the data by default.

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When you try to increase column size, it doesn't affect data. while decreasing column size, it should be affected