fixes #865

Author: wumpz

src/main/java/net/sf/jsqlparser/expression/AnalyticExpression.java

@@ -88,7 +88,14 @@ public ExpressionList getPartitionExpressionList() {
     }
 
     public void setPartitionExpressionList(ExpressionList partitionExpressionList) {
-        partitionBy.setPartitionExpressionList(partitionExpressionList);
+        setPartitionExpressionList(partitionExpressionList, false);
+    }
+    public void setPartitionExpressionList(ExpressionList partitionExpressionList, boolean brackets) {
+        partitionBy.setPartitionExpressionList(partitionExpressionList, brackets);
+    }
+    
+    public boolean isPartitionByBrackets() {
+        return partitionBy.isBrackets();
     }
 
     public String getName() {

src/main/java/net/sf/jsqlparser/expression/PartitionByClause.java

@@ -14,21 +14,31 @@
 
 public class PartitionByClause {
     ExpressionList partitionExpressionList;
+    boolean brackets = false;
 
     public ExpressionList getPartitionExpressionList() {
         return partitionExpressionList;
     }
-
+    
     public void setPartitionExpressionList(ExpressionList partitionExpressionList) {
+        setPartitionExpressionList(partitionExpressionList, false);
+    }
+
+    public void setPartitionExpressionList(ExpressionList partitionExpressionList, boolean brackets) {
         this.partitionExpressionList = partitionExpressionList;
+        this.brackets = brackets;
     }
 
     void toStringPartitionBy(StringBuilder b) {
         if (partitionExpressionList != null && !partitionExpressionList.getExpressions().isEmpty()) {
             b.append("PARTITION BY ");
             b.append(PlainSelect.
-                    getStringList(partitionExpressionList.getExpressions(), true, false));
+                    getStringList(partitionExpressionList.getExpressions(), true, brackets));
             b.append(" ");
         }
     }
+    
+    public boolean isBrackets() {
+        return brackets;
+    }
 }

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

@@ -216,8 +216,8 @@ public void visit(FullTextSearch fullTextSearch) {
                 columnsListCommaSeperated += ",";
             }
         }
-        buffer.append("MATCH (" + columnsListCommaSeperated + ") AGAINST (" + fullTextSearch.getAgainstValue() +
-                (fullTextSearch.getSearchModifier() != null ? " " + fullTextSearch.getSearchModifier() : "") + ")");
+        buffer.append("MATCH (" + columnsListCommaSeperated + ") AGAINST (" + fullTextSearch.getAgainstValue()
+                + (fullTextSearch.getSearchModifier() != null ? " " + fullTextSearch.getSearchModifier() : "") + ")");
     }
 
     @Override
@@ -654,13 +654,19 @@ public void visit(AnalyticExpression aexpr) {
 
         if (partitionExpressionList != null && !partitionExpressionList.getExpressions().isEmpty()) {
             buffer.append("PARTITION BY ");
+            if (aexpr.isPartitionByBrackets()) {
+                buffer.append("(");
+            }
             List<Expression> expressions = partitionExpressionList.getExpressions();
             for (int i = 0; i < expressions.size(); i++) {
                 if (i > 0) {
                     buffer.append(", ");
                 }
                 expressions.get(i).accept(this);
             }
+            if (aexpr.isPartitionByBrackets()) {
+                buffer.append(")");
+            }
             buffer.append(" ");
         }
         if (orderByElements != null && !orderByElements.isEmpty()) {

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

@@ -3114,18 +3114,20 @@ AnalyticExpression AnalyticExpression(Function function) :
     WindowElement windowElement = null;
     //KeepExpression keep = null;
     //boolean distinct = false;
-    //boolean ignoreNulls = false;
+    boolean partitionByBrackets = false;
 }
 {
     (<K_OVER> {retval.setType(AnalyticType.OVER);} 
         | <K_WITHIN> <K_GROUP> {retval.setType(AnalyticType.WITHIN_GROUP);} )
 
     "("
-        [<K_PARTITION> <K_BY> expressionList=SimpleExpressionList() ]
+        [<K_PARTITION> <K_BY> 
+            (LOOKAHEAD(3) expressionList=SimpleExpressionList() | "(" {partitionByBrackets = true;} expressionList=SimpleExpressionList() ")" ) 
+        ]
         [olist=OrderByElements() [windowElement = WindowElement() ] ]
 
     {
-        retval.setPartitionExpressionList(expressionList);
+        retval.setPartitionExpressionList(expressionList, partitionByBrackets);
         retval.setOrderByElements(olist);
         retval.setWindowElement(windowElement);
     }

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

@@ -3871,4 +3871,10 @@ public void testStartKeyword() throws JSQLParserException {
     public void testSizeKeywordIssue867() throws JSQLParserException {
         assertSqlCanBeParsedAndDeparsed("SELECT size FROM mytable");
     }
+    
+    @Test
+    public void testPartitionByWithBracketsIssue865() throws JSQLParserException {
+        assertSqlCanBeParsedAndDeparsed("SELECT subject_id, student_id, sum(mark) OVER (PARTITION BY subject_id, student_id ) FROM marks");
+        assertSqlCanBeParsedAndDeparsed("SELECT subject_id, student_id, sum(mark) OVER (PARTITION BY (subject_id, student_id) ) FROM marks");
+    }
 }