diff --git a/base/src/org/compiere/dbPort/Convert_PostgreSQL.java b/base/src/org/compiere/dbPort/Convert_PostgreSQL.java
index 01257985cb..6d428a670a 100644
--- a/base/src/org/compiere/dbPort/Convert_PostgreSQL.java
+++ b/base/src/org/compiere/dbPort/Convert_PostgreSQL.java
@@ -15,11 +15,9 @@ package org.compiere.dbPort;
 
 import java.math.BigDecimal;
 import java.util.ArrayList;
-import java.util.Iterator;
 import java.util.Map;
 import java.util.TreeMap;
 import java.util.Vector;
-import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 import java.util.StringTokenizer;
 import org.compiere.util.CLogger;
@@ -791,51 +789,6 @@ public class Convert_PostgreSQL extends Convert_SQL92 {
 		return result;
 	}
 	
-	private boolean isOperator(char c)
-	{
-		if ('=' == c)
-			return true;
-		else if ('<' == c)
-			return true;
-		else if ('>' == c)
-			return true;
-		else if ('|' == c)
-			return true;
-		else if ('(' == c)
-			return true;
-		else if (')' == c)
-			return true;
-		else if ('+' == c)
-			return true;
-		else if ('-' == c)
-			return true;
-		else if ('*' == c)
-			return true;
-		else if ('/' == c)
-			return true;
-		else if ('!' == c)
-			return true;
-		else if (',' == c)
-			return true;
-		else if ('?' == c)
-			return true;
-		else if ('#' == c)
-			return true;
-		else if ('@' == c)
-			return true;
-		else if ('~' == c)
-			return true;
-		else if ('&' == c)
-			return true;
-		else if ('^' == c)
-			return true;
-		else if ('!' == c)
-			return true;
-		else
-			return false;
-	}
-	
-	
 	/**
 	 * Check if token is a valid sql identifier
 	 * @param token
diff --git a/base/src/org/compiere/dbPort/Convert_PostgreSQLTest.java b/base/src/org/compiere/dbPort/Convert_PostgreSQLTest.java
index 19b4cfff53..1c86efc02a 100644
--- a/base/src/org/compiere/dbPort/Convert_PostgreSQLTest.java
+++ b/base/src/org/compiere/dbPort/Convert_PostgreSQLTest.java
@@ -336,5 +336,17 @@ public final class Convert_PostgreSQLTest extends TestCase{
 		sqe = "SELECT supplier_name, CASE WHEN supplier_id=10000 THEN 'IBM' WHEN supplier_id=10001 THEN 'Microsoft' WHEN supplier_id=10002 THEN 'Hewlett Packard' ELSE 'Gateway' END FROM suppliers";
 		r = convert.convert(sql);
 		assertEquals(sqe, r[0]);
+		
+		//doc_matchinv update average cost, bug [ 1742835 ]
+		sql = "UPDATE M_Product_Costing "
+		+ "SET CostAverage = CostAverageCumAmt/DECODE(CostAverageCumQty, 0,1, CostAverageCumQty) "
+		+ "WHERE C_AcctSchema_ID=0"
+		+ " AND M_Product_ID=0";
+		sqe = "UPDATE M_Product_Costing "
+			+ "SET CostAverage = CostAverageCumAmt/CASE WHEN CostAverageCumQty=0 THEN 1 ELSE CostAverageCumQty END "
+			+ "WHERE C_AcctSchema_ID=0"
+			+ " AND M_Product_ID=0";
+		r = convert.convert(sql);
+		assertEquals(sqe, r[0]);
 	}
 }
\ No newline at end of file
diff --git a/base/src/org/compiere/dbPort/Convert_SQL92.java b/base/src/org/compiere/dbPort/Convert_SQL92.java
index 0b3ccb7dbd..49794bd371 100644
--- a/base/src/org/compiere/dbPort/Convert_SQL92.java
+++ b/base/src/org/compiere/dbPort/Convert_SQL92.java
@@ -339,7 +339,8 @@ public abstract class Convert_SQL92 extends Convert {
 		int index = statement.toUpperCase().indexOf("DECODE", fromIndex);
 		if (index <= 0) return sqlStatement;
 		
-		if (Character.isWhitespace(statement.charAt(index - 1)) == false)
+		char previousChar = statement.charAt(index - 1);
+		if (!(Character.isWhitespace(previousChar) || isOperator(previousChar)))
 			return sqlStatement;
 		
 		String firstPart = statement.substring(0,index);
@@ -434,5 +435,54 @@ public abstract class Convert_SQL92 extends Convert {
 
 		return sqlStatement;
 	} // convertDelete
+	
+	/**
+	 * Is character a valid sql operator
+	 * @param c
+	 * @return boolean
+	 */
+	protected boolean isOperator(char c)
+	{
+		if ('=' == c)
+			return true;
+		else if ('<' == c)
+			return true;
+		else if ('>' == c)
+			return true;
+		else if ('|' == c)
+			return true;
+		else if ('(' == c)
+			return true;
+		else if (')' == c)
+			return true;
+		else if ('+' == c)
+			return true;
+		else if ('-' == c)
+			return true;
+		else if ('*' == c)
+			return true;
+		else if ('/' == c)
+			return true;
+		else if ('!' == c)
+			return true;
+		else if (',' == c)
+			return true;
+		else if ('?' == c)
+			return true;
+		else if ('#' == c)
+			return true;
+		else if ('@' == c)
+			return true;
+		else if ('~' == c)
+			return true;
+		else if ('&' == c)
+			return true;
+		else if ('^' == c)
+			return true;
+		else if ('!' == c)
+			return true;
+		else
+			return false;
+	}
 
 }