The db2 command starts the command line processor. The CLP is used to execute database utilities, SQL statements and online help. It offers a variety of command options, and can be be started in:
| Note: | On Windows NT, db2cmd - Open DB2 Command Window opens the CLP-enabled DB2 window, and initializes the DB2 command line environment. Issuing this command is equivalent to clicking on the DB2 Command Window icon. |
QUIT stops the command line processor. TERMINATE also stops the command line processor, but removes the associated back-end process and frees any memory that is being used. TERMINATE is recommended if the database has been stopped, or if database configuration parameters have been changed.
| Note: | Existing connections should be reset before terminating the CLP. |
The shell command (!), allows operating system commands to be executed from the interactive or the batch mode on UNIX based systems, and on OS/2 or the Windows operating system (!ls on UNIX, and !dir on OS/2 or the Windows operating system, for example).
| Note: | Shell command support is not available on Windows 3.1. |
Authorization
None
>>-db2----+------------------------------------------------+---><
'--.-------------------. |
V | |
+ --+--------------+--+---+-------------------+-+
| '-option-flag--' +-db2-command-------+ |
| +-sql-statement-----+ |
| '-?--+------------+-' |
| +-phrase-----+ |
| +-message----+ |
| +-sqlstate---+ |
| '-class-code-' |
'-----comment------------------------------------'
|
Command Parameters
? options requests a description and the current settings of the CLP options. ? help requests information about reading the online help syntax diagrams.
| Note: | In each case, a blank space must separate the question mark (?) from the variable name. |
The CLP command options can be specified by setting the command line processor DB2OPTIONS environment variable (which must be in uppercase), or with command line flags.
Users can set options for an entire session using DB2OPTIONS.
View the current settings for the option flags and the value of DB2OPTIONS using LIST COMMAND OPTIONS. Change an option setting from the interactive input mode or a command file using UPDATE COMMAND OPTIONS.
The command line processor sets options in the following order:
Table 1 summarizes the CLP option flags. These options can be
specified in almost any sequence and combination. To turn an option on,
prefix the corresponding option letter with a minus sign (-). To turn
an option off, either prefix the option letter with a minus sign and follow
the option letter with another minus sign, or prefix the option letter with a
plus sign (+). For example, -c turns the auto-commit
option on, and either -c- or +c turns it
off. These option letters are not case sensitive, that is,
-a and -A are equivalent.
| Option Flag | Description | Default Setting |
|---|---|---|
| -a | This option tells the command line processor to display SQLCA data. | OFF |
| -c | This option tells the command line processor to automatically commit SQL statements. | ON |
| -e{c&splitvbar.s} | This option tells the command line processor to display SQLCODE or SQLSTATE. These options are mutually exclusive. | OFF |
| -ffilename | This option tells the command line processor to read command input from a file instead of from standard input. | OFF |
| -lfilename | This option tells the command line processor to log commands in a history file. | OFF |
| -o | This option tells the command line processor to display output data and messages to standard output. | ON |
| -p | This option tells the command line processor to display a command line processor prompt when in interactive input mode. | ON |
| -rfilename | This option tells the command line processor to write the report generated by a command to a file. | OFF |
| -s | This option tells the command line processor to stop execution if errors occur while executing commands in a batch file or in interactive mode. | OFF |
| -t | This option tells the command line processor to use a semicolon (;) as the statement termination character. | OFF |
| -tdx | This option tells the command line processor to define and to use x as the statement termination character. | OFF |
| -v | This option tells the command line processor to echo command text to standard output. | OFF |
| -w | This option tells the command line processor to display SQL statement warning messages. | ON |
| -zfilename | This option tells the command line processor to redirect all output to a file. It is similar to the -r option, but includes any messages or error codes with the output. | OFF |
Example
The AIX command:
export DB2OPTIONS='+a -c +ec -o -p'
sets the following default settings for the session:
Display SQLCA - off Auto Commit - on Display SQLCODE - off Display Output - on Display Prompt - on |
The following is a detailed description of these options:
The default setting for this command option is OFF (+a or -a-).
The -o and the -r options affect the -a option; see the option descriptions for details.
The default setting for this command option is ON.
The auto-commit option does not affect any other command line processor option.
Example: Consider the following scenario:
The SQL statement in step 4 fails because there is no column named C2 in table A. Since that statement was issued with auto-commit ON (default), it rolls back not only the statement in step 4, but also the one in step 3, because the latter was issued with auto-commit OFF. The command:
db2 list tables
then returns an empty list.
The default setting for this command option is OFF (+e or -e-).
The -o and the -r options affect the -e option; see the option descriptions for details.
The display SQLCODE/SQLSTATE option does not affect any other command line processor option.
Example: To retrieve SQLCODE from the command line processor running on AIX, enter:
sqlcode=&rprime.db2 -ec +o db2-command&rprime.
When other options are combined with option -f, option -f must be specified last. For example:
db2 -tvf filename
| Note: | This option cannot be changed from within the interactive mode. |
The default setting for this command option is OFF (+f or -f-).
Commands are processed until QUIT or TERMINATE is issued, or an end-of-file is encountered.
If both this option and a database command are specified, the command line processor does not process any commands, and an error message is returned.
Input file lines which begin with the comment characters -- are treated as comments by the command line processor. Comment characters must be the first non-blank characters on a line.
If the -ffilename option is specified, the -p option is ignored.
The read from input file option does not affect any other command line processor option.
When other options are combined with option -l, option -l must be specified last. For example:
db2 -tvl filename
The default setting for this command option is OFF (+l or -l-).
The log commands in history file option does not affect any other command line processor option.
The default setting for this command option is ON.
The interactive mode start-up information is not affected by this option. Output data consists of report output from the execution of the user-specified command, and SQLCA data (if requested).
The following options may be affected by the +o option:
If both -o and -e options are specified, the data and either the SQLCODE or the SQLSTATE are displayed on the screen.
If both -o and -v options are specified, the data is displayed, and the text of each command issued is echoed to the screen.
The display output option does not affect any other command line processor option.
The default setting for this command option is ON.
Turning the prompt off is useful when commands are being piped to the command line processor. For example, a file containing CLP commands could be executed by issuing:
db2 +p < myfile.clp
The -p option is ignored if the -ffilename option is specified.
The display DB2 interactive prompt option does not affect any other command line processor option.
The default setting for this command option is OFF (+r or -r-).
If the -a option is specified, SQLCA data is written to the file.
The -r option does not affect the -e option. If the -e option is specified, SQLCODE or SQLSTATE is written to standard output, not to a file.
If -rfilename is set in DB2OPTIONS, the user can set the +r (or -r-) option from the command line to prevent output data for a particular command invocation from being written to the file.
The save to report file option does not affect any other command line processor option.
The default setting for this command option is OFF (+s or -s-). This setting causes the command line processor to display error messages, continue execution of the remaining commands, and to stop execution only if a system error occurs (return code 8).
The following table summarizes this behavior:
Table 2. CLP Return Codes and Command Execution
| Return Code | -s Option Set | +s Option Set |
|---|---|---|
| 0 (success) | execution continues | execution continues |
| 1 (0 rows selected) | execution continues | execution continues |
| 2 (warning) | execution continues | execution continues |
| 4 (DB2 or SQL error) | execution stops | execution continues |
| 8 (System error) | execution stops | execution stops |
| Note: | This option cannot be changed from within the interactive mode. |
The default setting for this command option is OFF (+t or -t-).
To define a termination character, use -td followed by the chosen termination character. For example, -tdx sets x as the statement termination character.
The termination character cannot be used to concatenate multiple statements from the command line, since only the last non-blank character on each input line is checked for a termination symbol.
The statement termination character option does not affect any other command line processor option.
The default setting for this command option is OFF (+v or -v-).
The -v option has no effect if +o (or -o-) is specified.
The verbose output option does not affect any other command line processor option.
The default setting for this command option is ON.
The default setting for this command option is OFF (+z or -z-).
If the -a option is specified, SQLCA data is written to the file.
The -z option does not affect the -e option. If the -e option is specified, SQLCODE or SQLSTATE is written to standard output, not to a file.
If -zfilename is set in DB2OPTIONS, the user can set the +z (or -z-) option from the command line to prevent output data for a particular command invocation from being written to the file.
The save all output to file option does not affect any other command line processor option.
Return Codes
When the command line processor finishes processing a command or an SQL statement, it returns an exit (or return) code. These codes are transparent to users executing CLP functions from the command line, but they can be retrieved when those functions are executed from a shell script.
For example, the following Bourne shell script executes the GET DATABASE MANAGER CONFIGURATION command, then inspects the CLP return code:
db2 get database manager configuration if ["$?" = "0"] then echo "OK!" fi
The return code can be one of the following:
The command line processor does not provide a return code while a user is executing statements from interactive mode, or while input is being read from a file (using the -f option).
A return code is available only after the user quits interactive mode, or when processing of an input file ends. In these cases, the return code is the logical OR of the distinct codes returned from the individual commands or statements executed to that point.
For example, if a user in interactive mode issues commands resulting in return codes of 0, 1, and 2, a return code of 3 will be returned after the user quits interactive mode. The individual codes 0, 1, and 2 are not returned. Return code 3 tells the user that during interactive mode processing, one or more commands returned a 1, and one or more commands returned a 2.
A return code of 4 results from a negative SQLCODE returned by a DB2 command or an SQL statement. A return code of 8 results only if the command line processor encounters a system error.
If commands are issued from an input file or in interactive mode, and the command line processor experiences a system error (return code 8), command execution is halted immediately. If one or more DB2 commands or SQL statements end in error (return code 4), command execution stops if the -s (Stop Execution on Command Error) option is set; otherwise, execution continues.