[CALCITE-6337] Distinguish naked measure support between inside and o…

…utside aggregation

Split nakedMeasures flag into two flags:
- nakedMeasuresInsideAggregatingQuery : allowed in group-by queries
- nakedMeasuresOutsideAggregatingQuery : allowed in non-group-by queries

The existing nakedMeasures flag is marked as deprecated. Its functionality
is equivalent to setting the above two flags to the same value.

core/src/main/java/org/apache/calcite/sql/validate/AggChecker.java

@@ -106,7 +106,7 @@ boolean isMeasureExp(SqlNode e) {
       return null;
     }
 
-    if (!validator.config().nakedMeasures()
+    if (!validator.config().nakedMeasuresInAggregateQuery()
         && isMeasureExp(id)) {
       SqlNode originalExpr = validator.getOriginal(id);
       throw validator.newValidationError(originalExpr,

core/src/main/java/org/apache/calcite/sql/validate/SqlValidator.java

@@ -912,15 +912,39 @@ interface Config {
      */
     Config withLenientOperatorLookup(boolean lenient);
 
-    /** Returns whether the validator allows measures to be used without the
-     * AGGREGATE function. Default is true. */
-    @Value.Default default boolean nakedMeasures() {
+    /** Returns whether the validator allows measures to be used without
+     * AGGREGATE function in a non-aggregate query. Default is true.
+     */
+    @Value.Default default boolean nakedMeasuresInNonAggregateQuery() {
       return true;
     }
 
+    /** Sets whether the validator allows measures to be used without AGGREGATE
+     * function in a non-aggregate query.
+     */
+    Config withNakedMeasuresInNonAggregateQuery(boolean value);
+
+    /** Returns whether the validator allows measures to be used without
+     * AGGREGATE function in an aggregate query. Default is true.
+     */
+    @Value.Default default boolean nakedMeasuresInAggregateQuery() {
+      return true;
+    }
+
+    /** Sets whether the validator allows measures to be used without AGGREGATE
+     * function in an aggregate query.
+     */
+    Config withNakedMeasuresInAggregateQuery(boolean value);
+
     /** Sets whether the validator allows measures to be used without the
-     * AGGREGATE function. */
-    Config withNakedMeasures(boolean nakedMeasures);
+     * AGGREGATE function inside or outside aggregate queries.
+     * Deprecated: use the inside / outside variants instead.
+     */
+    @Deprecated // to be removed before 1.38
+    default Config withNakedMeasures(boolean nakedMeasures) {
+      return withNakedMeasuresInAggregateQuery(nakedMeasures)
+              .withNakedMeasuresInNonAggregateQuery(nakedMeasures);
+    }
 
     /** Returns whether the validator supports implicit type coercion. */
     @Value.Default default boolean typeCoercionEnabled() {

core/src/main/java/org/apache/calcite/sql/validate/SqlValidatorImpl.java

@@ -2852,7 +2852,7 @@ private void registerQuery(
         }
       }
 
-      // If this is an aggregating query, the SELECT list and HAVING
+      // If this is an aggregate query, the SELECT list and HAVING
       // clause use a different scope, where you can only reference
       // columns which are in the GROUP BY clause.
       SqlValidatorScope aggScope = selectScope;
@@ -2888,7 +2888,7 @@ private void registerQuery(
         registerSubQueries(orderScope, orderList);
 
         if (!isAggregate(select)) {
-          // Since this is not an aggregating query,
+          // Since this is not an aggregate query,
           // there cannot be any aggregates in the ORDER BY clause.
           SqlNode agg = aggFinder.findAgg(orderList);
           if (agg != null) {
@@ -4826,10 +4826,10 @@ private void validateExpr(SqlNode expr, SqlValidatorScope scope) {
       }
     }
 
-    // Unless 'naked measures' are enabled, a non-aggregating query cannot
-    // reference measure columns. (An aggregating query can use them as
+    // Unless 'naked measures' are enabled, a non-aggregate query cannot
+    // reference measure columns. (An aggregate query can use them as
     // argument to the AGGREGATE function.)
-    if (!config.nakedMeasures()
+    if (!config.nakedMeasuresInNonAggregateQuery()
         && !(scope instanceof AggregatingScope)
         && scope.isMeasureRef(expr)) {
       throw newValidationError(expr,

core/src/test/java/org/apache/calcite/test/SqlValidatorTest.java

@@ -2866,7 +2866,7 @@ void testWinPartClause() {
         .fails("OVER clause is necessary for window functions");
 
     // With [CALCITE-1340], the validator would see RANK without OVER,
-    // mistakenly think this is an aggregating query, and wrongly complain
+    // mistakenly think this is an aggregate query, and wrongly complain
     // about the PARTITION BY: "Expression 'DEPTNO' is not being grouped"
     winSql("select cume_dist() over w , ^rank()^\n"
         + "from emp\n"
@@ -3874,8 +3874,19 @@ private void checkNegWindow(String s, String msg) {
     SqlValidatorFixture f =
         fixture().withExtendedCatalog()
             .withOperatorTable(operatorTableFor(SqlLibrary.CALCITE));
-    SqlValidatorFixture f2 =
-        f.withValidatorConfig(c -> c.withNakedMeasures(false));
+
+    SqlValidatorFixture fNakedInsideOnly =
+        f.withValidatorConfig(c ->
+            c.withNakedMeasuresInAggregateQuery(true)
+                .withNakedMeasuresInNonAggregateQuery(false));
+    SqlValidatorFixture fNakedOutsideOnly =
+        f.withValidatorConfig(c ->
+            c.withNakedMeasuresInNonAggregateQuery(true)
+                .withNakedMeasuresInAggregateQuery(false));
+    SqlValidatorFixture fNoNakedMeasures =
+        f.withValidatorConfig(c ->
+            c.withNakedMeasuresInNonAggregateQuery(false)
+                .withNakedMeasuresInAggregateQuery(false));
 
     final String measureIllegal =
         "Measure expressions can only occur within AGGREGATE function";
@@ -3890,28 +3901,36 @@ private void checkNegWindow(String s, String msg) {
         .ok();
 
     // Same SQL is invalid if naked measures are not enabled
-    f2.withSql(sql0).fails(measureIllegal);
+    fNoNakedMeasures.withSql(sql0).fails(measureIllegal);
+    fNakedOutsideOnly.withSql(sql0).fails(measureIllegal);
+    fNakedInsideOnly.withSql(sql0).isAggregate(is(true)).ok();
 
     // Similarly, with alias
     final String sql1b = "select deptno, ^count_plus_100^ as x\n"
         + "from empm\n"
         + "group by deptno";
     f.withSql(sql1b).isAggregate(is(true)).ok();
-    f2.withSql(sql1b).fails(measureIllegal);
+    fNoNakedMeasures.withSql(sql1b).fails(measureIllegal);
+    fNakedOutsideOnly.withSql(sql1b).fails(measureIllegal);
+    fNakedInsideOnly.withSql(sql1b).isAggregate(is(true)).ok();
 
     // Similarly, in an expression
     final String sql1c = "select deptno, deptno + ^count_plus_100^ * 2 as x\n"
         + "from empm\n"
         + "group by deptno";
     f.withSql(sql1c).isAggregate(is(true)).ok();
-    f2.withSql(sql1c).fails(measureIllegal);
+    fNoNakedMeasures.withSql(sql1c).fails(measureIllegal);
+    fNakedOutsideOnly.withSql(sql1c).fails(measureIllegal);
+    fNakedInsideOnly.withSql(sql1c).isAggregate(is(true)).ok();
 
     // Similarly, for a query that is an aggregate query because of another
     // aggregate function.
     final String sql1 = "select count(*), ^count_plus_100^\n"
         + "from empm";
     f.withSql(sql1).isAggregate(is(true)).ok();
-    f2.withSql(sql1).fails(measureIllegal);
+    fNoNakedMeasures.withSql(sql1).fails(measureIllegal);
+    fNakedInsideOnly.withSql(sql1).isAggregate(is(true)).ok();
+    fNakedOutsideOnly.withSql(sql1).fails(measureIllegal);
 
     // A measure in a non-aggregate query.
     // Using a measure should not make it an aggregate query.
@@ -3924,7 +3943,9 @@ private void checkNegWindow(String s, String msg) {
             + "MEASURE<INTEGER NOT NULL> NOT NULL COUNT_PLUS_100, "
             + "VARCHAR(20) NOT NULL ENAME) NOT NULL")
         .isAggregate(is(false));
-    f2.withSql(sql2).fails(measureIllegal2);
+    fNoNakedMeasures.withSql(sql2).fails(measureIllegal2);
+    fNakedInsideOnly.withSql(sql2).fails(measureIllegal2);
+    fNakedOutsideOnly.withSql(sql2).isAggregate(is(false)).ok();
 
     // as above, wrapping the measure in AGGREGATE
     final String sql3 = "select deptno, aggregate(count_plus_100) as x, ename\n"