ALTER SESSION

Function

ALTER SESSION defines or modifies the conditions or parameters that affect the current session. Modified session parameters are kept until the current session is disconnected.

Precautions

• If the START TRANSACTION statement is not executed before the SET TRANSACTION statement, the transaction is ended instantly and the statement does not take effect.
• You can use the transaction_mode(s) method declared in the START TRANSACTION statement to avoid using the SET TRANSACTION statement.

Syntax

• Set transaction parameters of a session.

  1 2	ALTER SESSION SET [ SESSION CHARACTERISTICS AS ] TRANSACTION { ISOLATION LEVEL { READ COMMITTED | READ UNCOMMITTED } | { READ ONLY | READ WRITE } } [, ...] ;

• Set other running parameters of a session.

  1 2 3 4 5 6 7 8 9 10

  ALTER SESSION SET {{config_parameter { { TO | = } { value | DEFAULT } | FROM CURRENT }} | CURRENT_SCHEMA [ TO | = ] { schema | DEFAULT } | TIME ZONE time_zone | SCHEMA schema | NAMES encoding_name | ROLE role_name PASSWORD 'password' | SESSION AUTHORIZATION { role_name PASSWORD 'password' | DEFAULT } | XML OPTION { DOCUMENT | CONTENT } } ;

Parameter Description

For details about the descriptions of parameters related to ALTER SESSION, see Parameter Description of the SET syntax.

Examples

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36

-- Create the ds schema.
openGauss=# CREATE SCHEMA ds;

-- Set the search path of a schema.
openGauss=# SET SEARCH_PATH TO ds, public;

-- Set the time/date type to the traditional postgres format (date before month).
openGauss=# SET DATESTYLE TO postgres, dmy;

-- Set the character code of the current session to UTF8.
openGauss=# ALTER SESSION SET NAMES 'UTF8';

-- Set the time zone to Berkeley of California.
openGauss=# SET TIME ZONE 'PST8PDT';

-- Set the time zone to Italy.
openGauss=# SET TIME ZONE 'Europe/Rome';

-- Set the current schema.
openGauss=# ALTER SESSION SET CURRENT_SCHEMA TO tpcds;

-- Set XML OPTION to DOCUMENT.
openGauss=# ALTER SESSION SET XML OPTION DOCUMENT;

-- Create the role joe, and set the session role to joe.
openGauss=# CREATE ROLE joe WITH PASSWORD 'xxxxxxxxxxx';
openGauss=# ALTER SESSION SET SESSION AUTHORIZATION joe PASSWORD 'xxxxxxxxxxxx';

-- Switch to the default user.
openGauss=> ALTER SESSION SET SESSION AUTHORIZATION default;

-- Delete the ds schema.
openGauss=# DROP SCHEMA ds;

-- Delete the role joe.
openGauss=# DROP ROLE joe;

Helpful Links

SET