Added a way to have nested PRIOR conditions when using connect by @hannes92

querydsl-core/src/main/java/com/querydsl/core/types/Ops.java

@@ -118,7 +118,10 @@ public enum Ops implements Operator {
   NULLIF(Object.class),
 
   // subquery operations
-  EXISTS(Boolean.class);
+  EXISTS(Boolean.class),
+
+  // Oracle specific
+  PRIOR(Object.class);
 
   private final Class<?> type;
 

querydsl-core/src/main/java/com/querydsl/core/types/Templates.java

@@ -72,6 +72,7 @@ public String escapeForLike(String str) {
     add(Ops.SINGLETON, "{0}", Precedence.LIST);
     add(Ops.WRAPPED, "({0})");
     add(Ops.ORDER, "order()");
+    add(Ops.PRIOR, "{0}", Precedence.NOT_HIGH);
 
     // boolean
     add(Ops.AND, "{0} && {1}", Precedence.AND);

querydsl-core/src/main/java/com/querydsl/core/types/dsl/SimpleExpression.java

@@ -376,4 +376,13 @@ public CaseForEqBuilder<T> when(T other) {
   public CaseForEqBuilder<T> when(Expression<? extends T> other) {
     return new CaseForEqBuilder<T>(mixin, other);
   }
+
+  /**
+   * Create a {@code PRIOR this} expression
+   *
+   * @return PRIOR this
+   */
+  public SimpleExpression<T> prior() {
+    return Expressions.operation(this.getType(), Ops.PRIOR, this);
+  }
 }

querydsl-core/src/test/java/com/querydsl/core/CoverageTest.java

@@ -118,6 +118,7 @@ public void test() throws IllegalArgumentException, IllegalAccessException {
             Ops.COALESCE,
             Ops.ORDINAL, // TODO: add support
             Ops.MATCHES_IC,
+            Ops.PRIOR,
 
             // aggregation
             Ops.AggOps.AVG_AGG,

querydsl-sql/src/main/java/com/querydsl/sql/OracleTemplates.java

@@ -78,6 +78,7 @@ public OracleTemplates(char escape, boolean quote) {
     setCountViaAnalytics(true);
     setListMaxSize(1000);
 
+    setPrecedence(Precedence.HIGHEST, Ops.PRIOR);
     setPrecedence(Precedence.COMPARISON, Ops.EQ, Ops.EQ_IGNORE_CASE, Ops.NE);
     setPrecedence(
         Precedence.COMPARISON + 1,
@@ -95,6 +96,9 @@ public OracleTemplates(char escape, boolean quote) {
     add(Ops.ALIAS, "{0} {1}");
     add(SQLOps.NEXTVAL, "{0s}.nextval");
 
+    // Oracle specific
+    add(Ops.PRIOR, "prior {0}");
+
     // String
     add(Ops.INDEX_OF, "instrb({0},{1})-1", Precedence.ARITH_LOW);
     add(Ops.INDEX_OF_2ARGS, "instrb({0},{1},{2+'1'})-1", Precedence.ARITH_LOW);

querydsl-sql/src/test/java/com/querydsl/sql/oracle/OracleGrammarTest.java

@@ -25,5 +25,6 @@ public void constants() {
     assertThat(OracleGrammar.level).isNotNull();
     assertThat(OracleGrammar.rownum).isNotNull();
     assertThat(OracleGrammar.sysdate).isNotNull();
+    assertThat(OracleGrammar.rowid).isNotNull();
   }
 }

querydsl-sql/src/test/java/com/querydsl/sql/oracle/OracleQueryTest.java

@@ -42,19 +42,38 @@ public void connectByPrior() {
   }
 
   @Test
-  public void connectBy() {
-    query.connectByPrior(survey.name.isNull());
+  public void connectByPriorNew() {
+    query.connectBy(survey.name.prior().isNull());
     assertThat(toString(query))
         .isEqualTo(
             "from SURVEY survey connect by prior survey.NAME is null order by survey.NAME asc");
   }
 
+  @Test
+  public void connectByPriorWithSelect() {
+    query
+        .select(survey.name.prior().as("parent_name"))
+        .connectBy(survey.name.prior().isNull().and(survey.name2.isNotNull()));
+    assertThat(toString(query))
+        .isEqualTo(
+            "select prior survey.NAME parent_name from SURVEY survey connect by prior survey.NAME is"
+                + " null and survey.NAME2 is not null order by survey.NAME asc");
+  }
+
+  @Test
+  public void connectBy() {
+    query.connectBy(survey.name.isNull());
+    assertThat(toString(query))
+        .isEqualTo("from SURVEY survey connect by survey.NAME is null order by survey.NAME asc");
+  }
+
   @Test
   public void connectByNocyclePrior() {
     query.connectByNocyclePrior(survey.name.isNull());
     assertThat(toString(query))
         .isEqualTo(
-            "from SURVEY survey connect by nocycle prior survey.NAME is null order by survey.NAME asc");
+            "from SURVEY survey connect by nocycle prior survey.NAME is null order by survey.NAME"
+                + " asc");
   }
 
   @Test