Use the SET command to set or change runtime parameters.
Issue this command to change parameters during the database connection.
Syntax
Syntax for the SET
command:
SET <parameter> { TO | = } { <value> | '<value>' | DEFAULT }
Inputs
The SET command takes
the following inputs:
Table 1. SET inputs| Input |
Description |
| <parameter> |
The parameter for which a value is to be set.
These are described in Parameters: |
| <value> |
The value that is to be set for the parameter. - Specify DEFAULT to reset a parameter to its default value.
- Use single quotation marks:
- For values that are longer than 128 characters
- For values that contain blanks or special characters such as plus
and minus signs
- To prevent character strings from being converted to the default
case
Possible values for each parameter are described in Parameters: |
Parameters
You can use
the SET command to set the following parameters:
- TIME ZONE
- The time zone for the system:
- '<timezone>'
- A time zone specified as signed hours with optional minutes (for
example, '-08' or '+10:30') that indicates its offset from GMT. A
minus sign indicates that the zone is west of Greenwich. The range
of time zones is '-12:59' to '+13:00'.
- LOCAL
- The local timezone.
Syntax:
SET TIME ZONE { TO | = } { '<timezone>' | DEFAULT }
- DATESTYLE
- The datestyle option is intended only for porting applications.
To format your date/time values, use the to_char family of functions.
Specify
the date/time output style, the substyle, or both:
- Date/time output style
- The date/time output styles are:
- ISO
- Use ISO 8601-style dates and times (YYYY-MM-DD for dates; hh:mm:ss
for times). This is the default.
- SQL
- Use DD/MM/YYYY or MM/DD/YYYY for dates; hh:mm:ss for times. Which
date style is used depends on the substyle.
- German
- Use DD.MM.YYYY for dates; hh:mm:ss for times.
- Substyle
- The substyle determines both which date format is used for the
SQL output format and the preferred interpretation of ambiguous date
input:
- European
- Use DD/MM/YYYY for numeric date representations.
- US
- Use MM/DD/YYYY for numeric date representations.
Syntax:
SET DATESTYLE { TO | = }
{ <output_style> | <substyle> | <output_style>,<substyle> | DEFAULT }
You
can initialize the date format by setting the pgdatestyle environment
variable. If pgdatestyle is set in the frontend
environment of a client that is based on libpq, libpq automatically
sets datestyle to the value of pgdatestyle during
connection start.
- RANDOM_SEED
- The seed for the random number generator. The random function
uses this value. You can specify any floating-point number in the
range from 0 to 1. (If a number outside this range is used, this product
silently overflows.) This number is then multiplied by 2(31)-1.
Syntax:
SET RANDOM_SEED { TO | = } { <value> | DEFAULT }
You can also set the seed by starting the setseed function: select
setseed(value);
- LOAD_REPLAY_REGION
- Enables load continuation. The default is 0 (not enabled).
If
you set the load replay region, the system automatically continues
a load after the system has been paused due to an SPU reset or failover.
The replay region is used to hold raw input data that will be parsed,
converted, packed into binary records, and sent to the respective
SPUs that have not be precommitted. When the system resumes from a
paused state, the system re-parses, re-converts, re-packs, and re-sends
to the SPUs all the raw data in this region.
Syntax:
SET LOAD_REPLAY_REGION { TO | = } { 0 | 1 | DEFAULT }
- CLIENT_USER_ID
- The user ID under which the client is running. The value can be
up to 1024 characters. The default is an empty string ('').
Syntax:
SET CLIENT_USER_ID { TO | = } { <value> | '<value>' | DEFAULT }
- CLIENT_WORKSTATION_NAME
- The host name of the workstation on which the client runs. The
value can be up to 1024 characters. The default is an empty string
('').
Syntax:
SET CLIENT_WORKSTATION_NAME { TO | = } { <value> | '<value>' | DEFAULT }
- CLIENT_APPLICATION_NAME
- The name of the client. The value can be up to 1024 characters.
The default is an empty string ('').
Syntax:
SET CLIENT_APPLICATION_NAME { TO | = } { <value> | '<value>' | DEFAULT }
- CLIENT_ACCOUNTING_STRING
- The accounting string. The value can be up to 1024 characters.
The default is an empty string ('').
Syntax:
SET CLIENT_ACCOUNTING_STRING { TO | = } { <value> | '<value>' | DEFAULT }
Outputs
The SET command has
the following outputs:
Table 2. SET outputs| Output |
Description |
| SET VARIABLE |
The command was successful. |
| ERROR: not a valid option name: name |
The parameter you tried to set does not exist. |
| ERROR: permission denied |
You do not have correct access. You must be an administrator
to have access to certain settings. |
| ERROR: name can only be set at start-up |
Certain parameters were fixed after the server is started. |
Privileges
You must be an
administrator, or you must have the appropriate object privileges.
Usage
The following examples
provide sample usage.
- Set the time zone to Eastern Standard Time (EST):
MYDB.MYSCH(USER)=> SET TIME ZONE TO '-05';
- Set the substyle to European:
MYDB.MYSCH(USER)=> SET DATESTYLE TO European;
- Set the output style to ISO and the substyle to US:
MYDB.MYSCH(USER)=> SET DATESTYLE TO ISO,US;
- Seed the random number generator with the number 0.45:
MYDB.MYSCH(USER)=> SET RANDOM_SEED=0.45;
- Enable load continuation:
MYDB.MYSCH(USER)=> SET LOAD_REPLAY_REGION=1;
- Set the name of the client workstation to homer.sampcorp.com and
to prevent the value from being converted to the default case:
MYDB.MYSCH(USER)=> SET CLIENT_WORKSTATION_NAME TO 'homer.sampcorp.com'