[teiid-commits] teiid SVN: r4172 - in branches/7.4.x/connectors/translator-jdbc/src: test/java/org/teiid/translator/jdbc/oracle and 1 other directory.

[teiid-commits at lists.jboss.org]

Author: jolee
Date: 2012-06-11 15:39:16 -0400 (Mon, 11 Jun 2012)
New Revision: 4172

Modified:
   branches/7.4.x/connectors/translator-jdbc/src/main/java/org/teiid/translator/jdbc/oracle/OracleExecutionFactory.java
   branches/7.4.x/connectors/translator-jdbc/src/test/java/org/teiid/translator/jdbc/oracle/TestOracleTranslator.java
Log:
TEIID-2069  Optimze add LIMIT clause to SELECT within a Virtual Procedure using Oracle
backport from trunk,  slimmed to not include api changes.

Modified: branches/7.4.x/connectors/translator-jdbc/src/main/java/org/teiid/translator/jdbc/oracle/OracleExecutionFactory.java
===================================================================
--- branches/7.4.x/connectors/translator-jdbc/src/main/java/org/teiid/translator/jdbc/oracle/OracleExecutionFactory.java	2012-06-11 17:52:05 UTC (rev 4171)
+++ branches/7.4.x/connectors/translator-jdbc/src/main/java/org/teiid/translator/jdbc/oracle/OracleExecutionFactory.java	2012-06-11 19:39:16 UTC (rev 4172)
@@ -36,6 +36,7 @@
 import java.util.List;
 
 import org.teiid.language.*;
+import org.teiid.language.Comparison.Operator;
 import org.teiid.language.SQLConstants.Tokens;
 import org.teiid.language.SetQuery.Operation;
 import org.teiid.language.visitor.CollectorVisitor;
@@ -282,6 +283,20 @@
     	}
 		Limit limit = queryCommand.getLimit();
 		queryCommand.setLimit(null);
+		
+		if (command instanceof Select) {
+			Select select = (Select)command;
+ 			TableReference tr = select.getFrom().get(0);
+ 			if (tr instanceof NamedTable && isDual((NamedTable)tr)) {
+ 				if (limit.getRowOffset() > 0 || limit.getRowLimit() == 0) {
+ 					//no data
+ 					select.setWhere(new Comparison(new Literal(1, TypeFacility.RUNTIME_TYPES.INTEGER), new Literal(0, TypeFacility.RUNTIME_TYPES.INTEGER), Operator.EQ));
+ 					return null;
+ 				}
+ 				return null; //dual does not allow a limit
+ 			}
+		}
+		
     	List<Object> parts = new ArrayList<Object>();
     	parts.add("SELECT "); //$NON-NLS-1$
     	/*
@@ -324,6 +339,20 @@
 		}
 		return parts;
     }
+    
+    private boolean isDual(NamedTable table) {
+    	String groupName = null;
+    	AbstractMetadataRecord groupID = table.getMetadataObject();
+    	if(groupID != null) {              
+    		String nameInSource = groupID.getNameInSource();
+            if(nameInSource != null && nameInSource.length() > 0) {
+                groupName = nameInSource;
+            } 
+    	} else {
+    		groupName = table.getName();
+    	}
+    	return DUAL.equalsIgnoreCase(groupName);
+    }
 
     @Override
     public boolean useAsInGroupAlias(){
@@ -557,16 +586,9 @@
 
 			private void stripDualAlias(NamedTable table) {
 				if (table.getCorrelationName() != null) {
-    				String groupName = null;
-    				AbstractMetadataRecord groupID = table.getMetadataObject();
-                    if(groupID != null) {              
-                        groupName = getName(groupID);
-                    } else {
-                        groupName = table.getName();
-                    }
-                    if (DUAL.equalsIgnoreCase(groupName)) {
-                    	table.setCorrelationName(null);
-                    }
+					if (isDual(table)) {
+                     	table.setCorrelationName(null);
+					}
     			}
 			}
     		

Modified: branches/7.4.x/connectors/translator-jdbc/src/test/java/org/teiid/translator/jdbc/oracle/TestOracleTranslator.java
===================================================================
--- branches/7.4.x/connectors/translator-jdbc/src/test/java/org/teiid/translator/jdbc/oracle/TestOracleTranslator.java	2012-06-11 17:52:05 UTC (rev 4171)
+++ branches/7.4.x/connectors/translator-jdbc/src/test/java/org/teiid/translator/jdbc/oracle/TestOracleTranslator.java	2012-06-11 19:39:16 UTC (rev 4172)
@@ -664,6 +664,28 @@
             output);        
     }
     
+    @Test public void testDUALLimit() throws Exception {
+    	String input = "SELECT something FROM DUAL as g0 LIMIT 2"; //$NON-NLS-1$
+    	String output = "SELECT seq.nextval FROM DUAL"; //$NON-NLS-1$
+    	
+    	helpTestVisitor(getOracleSpecificMetadata(),
+    			input, 
+    			EMPTY_CONTEXT,
+    			null,
+    			output);
+    }
+    
+    @Test public void testDUALLimit1() throws Exception {
+    	String input = "SELECT something FROM DUAL as g0 LIMIT 1, 2"; //$NON-NLS-1$
+    	String output = "SELECT seq.nextval FROM DUAL WHERE 1 = 0"; //$NON-NLS-1$
+    	
+    	helpTestVisitor(getOracleSpecificMetadata(),
+    			input, 
+    			EMPTY_CONTEXT,
+    			null,
+    			output);
+    }    
+    
     /**
      * Test Oracle's rownum pseudo-column.  Not a real column, so it can't
      * be fully-qualified with a table name.  MM requires this column to be