svn commit: r421920 - /db/derby/code/trunk/java/engine/org/apache/derby/impl/sql/execute/InternalTriggerExecutionContext.java

[dj...@apache.org]

Author: djd
Date: Fri Jul 14 08:17:37 2006
New Revision: 421920

URL: http://svn.apache.org/viewvc?rev=421920&view=rev
Log:
DERBY-551 (partial) Adds more comments to InternalTriggerExecutionContext.validateStatement.
Patch submitted by Deepa Remesh

Modified:
    db/derby/code/trunk/java/engine/org/apache/derby/impl/sql/execute/InternalTriggerExecutionContext.java

Modified: db/derby/code/trunk/java/engine/org/apache/derby/impl/sql/execute/InternalTriggerExecutionContext.java
URL: http://svn.apache.org/viewvc/db/derby/code/trunk/java/engine/org/apache/derby/impl/sql/execute/InternalTriggerExecutionContext.java?rev=421920&r1=421919&r2=421920&view=diff
==============================================================================
--- db/derby/code/trunk/java/engine/org/apache/derby/impl/sql/execute/InternalTriggerExecutionContext.java (original)
+++ db/derby/code/trunk/java/engine/org/apache/derby/impl/sql/execute/InternalTriggerExecutionContext.java Fri Jul 14 08:17:37 2006
@@ -327,15 +327,21 @@
 	 */
 	public void validateStatement(ConstantAction constantAction) throws StandardException
 	{
-		// DDL statements are not allowed in triggers
+		// DDL statements are not allowed in triggers. Parser does not allow 
+		// DDL statements in a trigger's action statement. This runtime check
+		// is needed only for DDL statements executed by procedures within a 
+		// trigger context. 
 		if (constantAction instanceof DDLConstantAction) {
 			throw StandardException.newException(SQLState.LANG_NO_DDL_IN_TRIGGER, triggerd.getName(), constantAction.toString());
 		}
 		
-		/*
-		** No INSERT/UPDATE/DELETE for a before trigger.
-	 	*/
-		else if (triggerd.isBeforeTrigger() && 
+		// No INSERT/UPDATE/DELETE for a before trigger. Parser does not allow 
+		// these DML statements in a trigger's action statement in a before 
+		// trigger. Currently, parser does not disallow creation of before 
+		// triggers calling procedures that modify SQL data. This runtime check
+		// is needed to not allow execution of these DML statements by procedures
+		// within a before trigger context. 
+	 	else if (triggerd.isBeforeTrigger() && 
 				constantAction instanceof WriteCursorConstantAction)
 		{
 			throw StandardException.newException(SQLState.LANG_NO_DML_IN_TRIGGER, triggerd.getName(), targetTableName);