fixes #299

Author: wumpz

README.md

@@ -42,6 +42,7 @@ Also I would like to know about needed examples or documentation stuff.
 
 ## Extensions in the latest SNAPSHOT version 0.9.6
 
+* support for **SELECT UNIQUE**
 * first support for date literals like **TIMESTAMP'2004-04-30 04:05:34.56'**
 * support for **UPDATE RETURNING**
 * support for scalar time function, like **CURRENT_TIMESTAMP**

src/main/java/net/sf/jsqlparser/statement/select/Distinct.java

@@ -29,6 +29,14 @@
 public class Distinct {
 
 	private List<SelectItem> onSelectItems;
+    private boolean useUnique = false;
+
+    public Distinct() {
+    }
+    
+    public Distinct(boolean useUnique) {
+        this.useUnique = useUnique;
+    } 
 
 	/**
 	 * A list of {@link SelectItem}s expressions, as in "select DISTINCT ON
@@ -44,9 +52,17 @@ public void setOnSelectItems(List<SelectItem> list) {
 		onSelectItems = list;
 	}
 
+    public boolean isUseUnique() {
+        return useUnique;
+    }
+
+    public void setUseUnique(boolean useUnique) {
+        this.useUnique = useUnique;
+    }
+
 	@Override
 	public String toString() {
-		String sql = "DISTINCT";
+		String sql = useUnique?"UNIQUE":"DISTINCT";
 
 		if (onSelectItems != null && !onSelectItems.isEmpty()) {
 			sql += " ON (" + PlainSelect.getStringList(onSelectItems) + ")";

src/main/java/net/sf/jsqlparser/util/deparser/SelectDeParser.java

@@ -73,7 +73,11 @@ public void visit(PlainSelect plainSelect) {
         }
 
         if (plainSelect.getDistinct() != null) {
-            buffer.append("DISTINCT ");
+            if (plainSelect.getDistinct().isUseUnique()) {
+                buffer.append("UNIQUE ");
+            } else {
+                buffer.append("DISTINCT ");
+            }
             if (plainSelect.getDistinct().getOnSelectItems() != null) {
                 buffer.append("ON (");
                 for (Iterator<SelectItem> iter = plainSelect.getDistinct().getOnSelectItems().iterator(); iter.hasNext();) {

src/main/jjtree/net/sf/jsqlparser/parser/JSqlParserCC.jjt

@@ -874,6 +874,10 @@ PlainSelect PlainSelect():
     			<K_DISTINCT> { Distinct distinct = new Distinct(); plainSelect.setDistinct(distinct); }
     				[ "ON" "(" distinctOn=SelectItemsList()  { plainSelect.getDistinct().setOnSelectItems(distinctOn); } ")" ]
     		)
+        |
+            (
+                <K_UNIQUE> { Distinct distinct = new Distinct(true); plainSelect.setDistinct(distinct); }
+            )
     ]
 
     [top = Top() { plainSelect.setTop(top);	} ]

src/test/java/net/sf/jsqlparser/test/select/SelectTest.java

@@ -2208,4 +2208,8 @@ public void testFunctionIssue284() throws JSQLParserException {
     public void testFunctionDateTimeValues() throws JSQLParserException {
         assertSqlCanBeParsedAndDeparsed("SELECT * FROM tab1 WHERE a > TIMESTAMP '2004-04-30 04:05:34.56'");
     }
+    
+    public void testUniqueInsteadOfDistinctIssue299() throws JSQLParserException {
+        assertSqlCanBeParsedAndDeparsed("SELECT UNIQUE trunc(timez(ludate)+ 8/24) bus_dt, j.object j_name , timez(j.starttime) START_TIME , timez(j.endtime) END_TIME FROM TEST_1 j", true);
+    }
 }