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In some versions of MySQL, the results from DESCRIBE include additional information showing access privilege information. I've not shown that here because it makes the lines too long to display without wrapping around.
The output looks pretty much as we'd expect, except that the information for the state column says its type is CHAR(2). That's odd; wasn't it declared as VARCHAR(2)? Yes, it was, but MySQL has silently changed the type from VARCHAR to CHAR. The reason for this has to do with efficiency of storage space for short character columns, which I won't go into here. If you want the details, check the discussion of the ALTER TABLE statement in Chapter 3, "MySQL SQL Syntax and Use." For our purposes here, there is no difference between the two types. The important thing is that the column stores two-character values.
If you issue a DESCRIBE member query, mysql will show you similar information for the member table.
DESCRIBE is useful when you forget the name of a column in a table or need to know its type or how wide it is and so on. It's also useful for finding out the order in which MySQL stores columns in table rows. That order is important when you use INSERT or LOAD DATA statements that expect column values to be listed in the default column order.
The information produced by DESCRIBE can be obtained in different ways. It may be abbreviated as DESC or written as an EXPLAIN or SHOW statement. The following statements are all synonymous:
DESCRIBE president;
DESC president;
EXPLAIN president;
SHOW COLUMNS FROM president;
SHOW FIELDS FROM president;
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