Database, table, index and column names

Database, table, index and column names all follow the same rules in MySQL.

A name may use alphanumeric characters from the default character set. This is by default ISO-8859-1 Latin1 but may be changed when compiling MySQL.

Since MySQL needs to be able to decide if something is a name or a number the following special cases occurs.

• A name can not consist of only numbers.
• A name may start with a number. This is a difference from many other systems!
• It is not recommended to use names like 1e. This is because expressions like 1e+1 may be interpreted like the expression 1e + 1 or the number 1e+1.

Punctuation characters like . and @ are not allowed in names since they will be used to extend MySQL.

In MySQL you can refer to a column with some of the following syntaxes:

• column
• table.column
• database.table.column
• table@database.column

If you are using 'column' or 'table.column' you will get an error if the name is not unique among the used tables!

Go to the first, previous, next, last section, table of contents.