Nested with items

README.md

@@ -57,10 +57,11 @@ Also I would like to know about needed examples or documentation stuff.
 
 ## Extensions in the latest SNAPSHOT version 4.1
 
-* support for **with** (ctl) for **delete**, **update** and **merge**
+* support for nested `WITH` CTEs
+* support for **with** (cte) for **delete**, **update** and **merge**
 * introduce a max depth to allow parsing complex expression lists without performance loss (thx to @manticore-projects)
 * allow all functions to have complex expressions as parameters (thx to @manticore-projects)
-** API change FunctionWithCondParams production removed
+* API change FunctionWithCondParams production removed
 * API change in ValuesStatement: the expression list is now hold as a ItemList and not as a List<Expression>
 * support for parser modification within **parseExpression** and **parseCondExpression**
 * support for table schema for foreign keys

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

@@ -14,14 +14,64 @@
 import java.util.Collections;
 import java.util.List;
 import java.util.Optional;
+import net.sf.jsqlparser.expression.operators.relational.ExpressionList;
+import net.sf.jsqlparser.expression.operators.relational.ItemsList;
 
 public class WithItem implements SelectBody {
 
     private String name;
     private List<SelectItem> withItemList;
-    private SelectBody selectBody;
+    private ItemsList itemsList;
+    private boolean useValues = true;
+    private boolean useBracketsForValues = false;
+
+    private SubSelect subSelect;
     private boolean recursive;
 
+    /**
+     * Get the values (as VALUES (...) or SELECT)
+     *
+     * @return the values of the insert
+     */
+    public ItemsList getItemsList() {
+        return itemsList;
+    }
+
+    public void setItemsList(ItemsList list) {
+        itemsList = list;
+    }
+
+    public boolean isUseValues() {
+        return useValues;
+    }
+
+    public void setUseValues(boolean useValues) {
+        this.useValues = useValues;
+    }
+
+    public WithItem withItemsList(ItemsList itemsList) {
+        this.setItemsList(itemsList);
+        return this;
+    }
+
+    public WithItem withUseValues(boolean useValues) {
+        this.setUseValues(useValues);
+        return this;
+    }
+
+    public boolean isUsingBracketsForValues() {
+        return useBracketsForValues;
+    }
+
+    public void setUseBracketsForValues(boolean useBracketsForValues) {
+        this.useBracketsForValues = useBracketsForValues;
+    }
+
+    public WithItem withUseBracketsForValues(boolean useBracketsForValues) {
+        this.setUseBracketsForValues(useBracketsForValues);
+        return this;
+    }
+
     public String getName() {
         return name;
     }
@@ -38,12 +88,12 @@ public void setRecursive(boolean recursive) {
         this.recursive = recursive;
     }
 
-    public SelectBody getSelectBody() {
-        return selectBody;
+    public SubSelect getSubSelect() {
+        return subSelect.withUseBrackets(false);
     }
 
-    public void setSelectBody(SelectBody selectBody) {
-        this.selectBody = selectBody;
+    public void setSubSelect(SubSelect subSelect) {
+        this.subSelect = subSelect.withUseBrackets(false);
     }
 
     /**
@@ -62,9 +112,26 @@ public void setWithItemList(List<SelectItem> withItemList) {
     @Override
     @SuppressWarnings({"PMD.CyclomaticComplexity"})
     public String toString() {
-        return (recursive ? "RECURSIVE " : "") + name + ((withItemList != null) ? " " + PlainSelect.
-                getStringList(withItemList, true, true) : "")
-                + " AS (" + selectBody + ")";
+        StringBuilder builder = new StringBuilder();
+        builder.append(recursive ? "RECURSIVE " : "");
+        builder.append(name);
+        builder.append(
+                (withItemList != null) ? " " + PlainSelect.getStringList(withItemList, true, true) : "");
+        builder.append(" AS ");
+
+        if (useValues) {
+            builder.append("(VALUES ");
+            ExpressionList expressionList = (ExpressionList) itemsList;
+            builder.append(
+                    PlainSelect.getStringList(expressionList.getExpressions(), true, useBracketsForValues));
+            builder.append(")");
+        } else {
+            builder.append(subSelect.isUseBrackets() ? "" : "(");
+            builder.append(subSelect);
+
+            builder.append(subSelect.isUseBrackets() ? "" : ")");
+        }
+        return builder.toString();
     }
 
     @Override
@@ -82,8 +149,8 @@ public WithItem withWithItemList(List<SelectItem> withItemList) {
         return this;
     }
 
-    public WithItem withSelectBody(SelectBody selectBody) {
-        this.setSelectBody(selectBody);
+    public WithItem withSubSelect(SubSelect subSelect) {
+        this.setSubSelect(subSelect);
         return this;
     }
 
@@ -103,8 +170,4 @@ public WithItem addWithItemList(Collection<? extends SelectItem> withItemList) {
         collection.addAll(withItemList);
         return this.withWithItemList(collection);
     }
-
-    public <E extends SelectBody> E getSelectBody(Class<E> type) {
-        return type.cast(getSelectBody());
-    }
 }

src/main/java/net/sf/jsqlparser/util/TablesNamesFinder.java

@@ -147,7 +147,7 @@ public List<String> getTableList(Expression expr) {
     @Override
     public void visit(WithItem withItem) {
         otherItemNames.add(withItem.getName().toLowerCase());
-        withItem.getSelectBody().accept(this);
+    withItem.getSubSelect().accept((ItemsListVisitor) this);
     }
 
     @Override

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

@@ -19,6 +19,7 @@
 import net.sf.jsqlparser.expression.OracleHint;
 import net.sf.jsqlparser.expression.SQLServerHints;
 import net.sf.jsqlparser.expression.operators.relational.ExpressionList;
+import net.sf.jsqlparser.expression.operators.relational.ItemsList;
 import net.sf.jsqlparser.expression.operators.relational.ItemsListVisitor;
 import net.sf.jsqlparser.expression.operators.relational.MultiExpressionList;
 import net.sf.jsqlparser.expression.operators.relational.NamedExpressionList;
@@ -240,7 +241,7 @@ public void visit(SelectExpressionItem selectExpressionItem) {
 
     @Override
     public void visit(SubSelect subSelect) {
-        buffer.append("(");
+        buffer.append(subSelect.isUseBrackets() ? "(" : "");
         if (subSelect.getWithItemsList() != null && !subSelect.getWithItemsList().isEmpty()) {
             buffer.append("WITH ");
             for (Iterator<WithItem> iter = subSelect.getWithItemsList().iterator(); iter.hasNext();) {
@@ -253,7 +254,7 @@ public void visit(SubSelect subSelect) {
             }
         }
         subSelect.getSelectBody().accept(this);
-        buffer.append(")");
+        buffer.append(subSelect.isUseBrackets() ? ")" : "");
         Alias alias = subSelect.getAlias();
         if (alias != null) {
             buffer.append(alias.toString());
@@ -484,9 +485,27 @@ public void visit(WithItem withItem) {
         if (withItem.getWithItemList() != null) {
             buffer.append(" ").append(PlainSelect.getStringList(withItem.getWithItemList(), true, true));
         }
-        buffer.append(" AS (");
-        withItem.getSelectBody().accept(this);
-        buffer.append(")");
+        buffer.append(" AS ");
+
+        if (withItem.isUseValues()) {
+            ItemsList itemsList = withItem.getItemsList();
+            boolean useBracketsForValues = withItem.isUsingBracketsForValues();
+            buffer.append("(VALUES ");
+
+            ExpressionList expressionList = (ExpressionList) itemsList;
+            buffer.append(
+                    PlainSelect.getStringList(expressionList.getExpressions(), true, useBracketsForValues));
+            buffer.append(")");
+        } else {
+            SubSelect subSelect = withItem.getSubSelect();
+            if (!subSelect.isUseBrackets()) {
+                buffer.append("(");
+            }
+            subSelect.accept((FromItemVisitor) this);
+            if (!subSelect.isUseBrackets()) {
+                buffer.append(")");
+            }
+        }
     }
 
     @Override

src/main/java/net/sf/jsqlparser/util/validation/validator/SelectValidator.java

@@ -287,7 +287,7 @@ public void visit(WithItem withItem) {
         if (isNotEmpty(withItem.getWithItemList())) {
             withItem.getWithItemList().forEach(wi -> wi.accept(this));
         }
-        withItem.getSelectBody().accept(this);
+        withItem.getSubSelect().accept(this);
     }
 
     @Override

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

@@ -1691,13 +1691,24 @@ WithItem WithItem() #WithItem:
     WithItem with = new WithItem();
     String name = null;
     List<SelectItem> selectItems = null;
-    SelectBody selectBody = null;
+    SubSelect select = null;
+
+    ExpressionList simpleExpressionList;
 }
 {
      [ <K_RECURSIVE> { with.setRecursive(true); } ] name=RelObjectName() { with.setName(name); }
      [ "(" selectItems=SelectItemsList() ")" { with.setWithItemList(selectItems); } ]
      <K_AS>
-     "(" selectBody = SelectBody() { with.setSelectBody(selectBody); } ")"
+    // if the next block looks alike an ExpressionList without Brackets, then parse as List
+    ( LOOKAHEAD( "(" <K_VALUES> SimpleExpressionList(true) ")" ) 
+        "(" <K_VALUES>
+            simpleExpressionList = SimpleExpressionList(true) { with.withUseBracketsForValues(false).setItemsList(simpleExpressionList); }
+        ")"
+
+    // Otherwise parse it as a SubSelect
+        | "(" select = SubSelect() { with.setSubSelect(select.withUseBrackets(false)); with.setUseValues(false); } ")"
+
+    )
      { return with; }
 }