INTERRUPT_STATEMENT

Interrupts the specified statement in a user session, rolls back the current transaction, and writes a success or failure message to the log file.

Sessions can be interrupted during statement execution. Only statements run by user sessions can be interrupted.

Syntax

INTERRUPT_STATEMENT( 'session‑id', statement‑id )

Parameters

session‑id

Identifies the session to interrupt. This identifier is unique within the cluster at any point in time.

statement‑id

Identifies the statement to interrupt. If the statement‑id is valid, the statement can be interrupted and INTERRUPT_STATEMENT returns a success message. Otherwise the system returns an error.

Privileges

Superuser

Messages

The following list describes messages you might encounter:

Message Meaning 
Statement interrupt sent. Check SESSIONS for progress.

This message indicates success.

 
Session <id> could not be successfully interrupted: session not found.

The session ID argument to the interrupt command does not match a running session.

 
Session <id> could not be successfully interrupted: statement not found.

The statement ID does not match (or no longer matches) the ID of a running statement (if any).

 
No interruptible statement running

The statement is DDL or otherwise non-interruptible.

 
Internal (system) sessions cannot be interrupted.

The session is internal, and only statements run by external sessions can be interrupted.

Examples

Two user sessions are open. RECORD 1 shows user session running SELECT FROM SESSION, and RECORD 2 shows user session running COPY DIRECT:

=> SELECT * FROM SESSIONS;
-[ RECORD 1 ]--------------+----------------------------------------------------
node_name                  | v_vmartdb_node0001
user_name                  | dbadmin
client_hostname            | 127.0.0.1:52110
client_pid                 | 4554
login_timestamp            | 2011-01-03 14:05:40.252625-05
session_id                 | stress04-4325:0x14
client_label               |
transaction_start          | 2011-01-03 14:05:44.325781
transaction_id             | 45035996273728326
transaction_description    | user dbadmin (select * from sessions;)
statement_start            | 2011-01-03 15:36:13.896288
statement_id               | 10
last_statement_duration_us | 14978
current_statement          | select * from sessions;
ssl_state                  | None
authentication_method      | Trust
-[ RECORD 2 ]--------------+----------------------------------------------------
node_name                  | v_vmartdb_node0003
user_name                  | dbadmin
client_hostname            | 127.0.0.1:56367
client_pid                 | 1191
login_timestamp            | 2011-01-03 15:31:44.939302-05
session_id                 | stress06-25663:0xbec
client_label               |
transaction_start          | 2011-01-03 15:34:51.05939
transaction_id             | 54043195528458775
transaction_description    | user dbadmin (COPY Mart_Fact FROM '/data/Mart_Fact.tbl' 
                             DELIMITER '|' NULL '\\n' DIRECT;)
statement_start            | 2011-01-03 15:35:46.436748
statement_id               | 5
last_statement_duration_us | 1591403
current_statement          | COPY Mart_Fact FROM '/data/Mart_Fact.tbl' DELIMITER '|' 
                             NULL '\\n' DIRECT;
ssl_state                  | None
authentication_method      | Trust

Interrupt the COPY DIRECT statement running in session stress06-25663:0xbec:

=> \x
Expanded display is off.
=> SELECT INTERRUPT_STATEMENT('stress06-25663:0x1537', 5);
                       interrupt_statement
------------------------------------------------------------------
 Statement interrupt sent. Check v_monitor.sessions for progress.
(1 row)

Verify that the interrupted statement is no longer active by looking at the current_statement column in the SESSIONS system table. This column becomes blank when the statement is interrupted:

=> SELECT * FROM SESSIONS;
-[ RECORD 1 ]--------------+----------------------------------------------------
node_name                  | v_vmartdb_node0001
user_name                  | dbadmin
client_hostname            | 127.0.0.1:52110
client_pid                 | 4554
login_timestamp            | 2011-01-03 14:05:40.252625-05
session_id                 | stress04-4325:0x14
client_label               |
transaction_start          | 2011-01-03 14:05:44.325781
transaction_id             | 45035996273728326
transaction_description    | user dbadmin (select * from sessions;)
statement_start            | 2011-01-03 15:36:13.896288
statement_id               | 10
last_statement_duration_us | 14978
current_statement          | select * from sessions;
ssl_state                  | None
authentication_method      | Trust
-[ RECORD 2 ]--------------+----------------------------------------------------
node_name                  | v_vmartdb_node0003
user_name                  | dbadmin
client_hostname            | 127.0.0.1:56367
client_pid                 | 1191
login_timestamp            | 2011-01-03 15:31:44.939302-05
session_id                 | stress06-25663:0xbec
client_label               |
transaction_start          | 2011-01-03 15:34:51.05939
transaction_id             | 54043195528458775
transaction_description    | user dbadmin (COPY Mart_Fact FROM '/data/Mart_Fact.tbl' 
                             DELIMITER '|' NULL '\\n' DIRECT;)
statement_start            | 2011-01-03 15:35:46.436748
statement_id               | 5
last_statement_duration_us | 1591403
current_statement          | 
ssl_state                  | None
authentication_method      | Trust

See Also