2026-03-12 21:01:38

tiddlywiki/Oracle - SQL Quarantine - example.md

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+> [Original article](https://oracle-base.com/articles/19c/sql-quarantine-19c)
+
+
+
+We can manually quarantine a statement based on SQL_ID or SQL_TEXT.  
+Both methods accept a PLAN_HASH_VALUE parameter, which allows us to quarantine a single execution plan.  
+If this is not specified, all execution plans for the statement are quarantined.
+
+
+	-- Quarantine all execution plans for a SQL_ID.
+	DECLARE
+	  l_sql_quarantine  VARCHAR2(100);
+	BEGIN
+	  l_sql_quarantine := sys.DBMS_SQLQ.create_quarantine_by_sql_id(
+	                        sql_id => 'gs59hr0xtjrf8'
+	                      );
+	  DBMS_OUTPUT.put_line('l_sql_quarantine=' || l_sql_quarantine);
+	END;
+	/
+
+
+SQL quarantine display:
+
+	set lines 256
+	COLUMN sql_text FORMAT A50 TRUNC
+	COLUMN plan_hash_value FORMAT 999999999999
+	COLUMN name FORMAT A30
+	COLUMN enabled FORMAT A3 HEAD "Ena"
+	COLUMN cpu_time FORMAT A10
+	COLUMN io_megabytes FORMAT A10
+	COLUMN io_requests FORMAT A10
+	COLUMN elapsed_time FORMAT A10
+	COLUMN io_logical FORMAT A10
+
+	select 
+		name, enabled,cpu_time, io_megabytes, io_requests, elapsed_time, io_logical, plan_hash_value, sql_text
+	from 
+		dba_sql_quarantine;
+
+
+The ALTER_QUARANTINE procedure allows us to alter the thresholds, to make them look more like automatically generated quarantines.  
+We can use the procedure to alter the following parameters:
+
+- CPU_TIME
+- ELAPSED_TIME
+- IO_MEGABYTES
+- IO_REQUESTS
+- IO_LOGICAL
+- ENABLED
+- AUTOPURGE
+
+Example of setting the CPU_TIME threshold for the manually created quarantines:
+
+	BEGIN
+	  DBMS_SQLQ.alter_quarantine(
+	    quarantine_name  =>  'SQL_QUARANTINE_8zpc9pwdmb8vr',
+	    parameter_name   =>  'CPU_TIME',
+	    parameter_value  =>  '1');
+	 END;
+	/