1.2 Typographical and Syntax Conventions

This manual uses certain typographical conventions:

  • Text in this style is used for SQL statements; database, table, and column names; program listings and source code; and environment variables. Example: To reload the grant tables, use the FLUSH PRIVILEGES statement.

  • Text in this style indicates input that you type in examples.

  • Text in this style indicates the names of executable programs and scripts, examples being mysql (the MySQL command-line client program) and mysqld (the MySQL server executable).

  • Text in this style is used for variable input for which you should substitute a value of your own choosing.

  • Text in this style is used for emphasis.

  • Text in this style is used in table headings and to convey especially strong emphasis.

  • Text in this style is used to indicate a program option that affects how the program is executed, or that supplies information that is needed for the program to function in a certain way. Example: The --host option (short form -h) tells the mysql client program the hostname or IP address of the MySQL server that it should connect to.

  • File names and directory names are written like this: The global my.cnf file is located in the /etc directory.

  • Character sequences are written like this: To specify a wildcard, use the % character.

When commands are shown that are meant to be executed from within a particular program, the prompt shown preceding the command indicates which command to use. For example, shell> indicates a command that you execute from your login shell, root-shell> is similar but should be executed as root, and mysql> indicates a statement that you execute from the mysql client program:

shell> type a shell command here
root-shell> type a shell command as root here
mysql> type a mysql statement here

In some areas different systems may be distinguished from each other to show that commands should be executed in two different environments. For example, while working with replication the commands might be prefixed with master and slave:

master> type a mysql command on the replication master here
slave> type a mysql command on the replication slave here

The shell is your command interpreter. On Unix, this is typically a program such as sh, csh, or bash. On Windows, the equivalent program is command.com or cmd.exe, typically run in a console window.

When you enter a command or statement shown in an example, do not type the prompt shown in the example.

Database, table, and column names must often be substituted into statements. To indicate that such substitution is necessary, this manual uses db_name, tbl_name, and col_name. For example, you might see a statement like this:

mysql> SELECT col_name FROM db_name.tbl_name;

This means that if you were to enter a similar statement, you would supply your own database, table, and column names, perhaps like this:

mysql> SELECT author_name FROM biblio_db.author_list;

SQL keywords are not case-sensitive and may be written in any lettercase. This manual uses uppercase.

In syntax descriptions, square brackets ([ and ]) indicate optional words or clauses. For example, in the following statement, IF EXISTS is optional:

DROP TABLE [IF EXISTS] tbl_name

When a syntax element consists of a number of alternatives, the alternatives are separated by vertical bars (|). When one member from a set of choices may be chosen, the alternatives are listed within square brackets ([ and ]):

TRIM([[BOTH | LEADING | TRAILING] [remstr] FROM] str)

When one member from a set of choices must be chosen, the alternatives are listed within braces ({ and }):

{DESCRIBE | DESC} tbl_name [col_name | wild]

An ellipsis (...) indicates the omission of a section of a statement, typically to provide a shorter version of more complex syntax. For example, SELECT ... INTO OUTFILE is shorthand for the form of SELECT statement that has an INTO OUTFILE clause following other parts of the statement.

An ellipsis can also indicate that the preceding syntax element of a statement may be repeated. In the following example, multiple reset_option values may be given, with each of those after the first preceded by commas:

RESET reset_option [,reset_option] ...

Commands for setting shell variables are shown using Bourne shell syntax. For example, the sequence to set the CC environment variable and run the configure command looks like this in Bourne shell syntax:

shell> CC=gcc ./configure

If you are using csh or tcsh, you must issue commands somewhat differently:

shell> setenv CC gcc
shell> ./configure