Should Numbers Be Quoted in MySQL Queries?

When Using MySQL: Should Numbers Be Quoted?

In MySQL, it is generally unnecessary to quote numbers. The database will automatically convert data types as needed.

Illustration:

Consider the following SQL statements:

CREATE DATABASE testdb CHARACTER SET 'utf8' COLLATE 'utf8_general_ci';
USE testdb;
CREATE TABLE test (id INT, str VARCHAR(100)) TYPE=innodb CHARACTER SET 'utf8' COLLATE 'utf8_general_ci';
INSERT INTO test VALUES (9, 'some string');

If you execute these statements, MySQL will correctly create the database and table.

Why Numbers Don't Need Quoting:

When selecting or inserting data, you can use either quoted or unquoted numbers. For example:

SELECT * FROM test WHERE id = '9';
INSERT INTO test VALUES ('11', 'some string');

These examples work because MySQL will automatically convert the string representations of numbers to their numeric equivalents.

Can All Data Types Be Inserted as Strings?

While MySQL can automatically convert numbers from strings, it does not support this behavior for all data types. For example, you cannot insert a string into a DATE column.

Cross-RDBMS Compatibility:

The behavior of automatically converting numbers from strings is specific to MySQL. Other RDBMS may require explicit typecasting or may not support the conversion altogether.

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