[CALCITE-6632] Wrong optimization because window missing constants in…

… digest

core/src/main/java/org/apache/calcite/rel/core/Window.java

@@ -163,6 +163,9 @@ public Window(RelOptCluster cluster, RelTraitSet traitSet, RelNode input,
     for (Ord<Group> window : Ord.zip(groups)) {
       pw.item("window#" + window.i, window.e.toString());
     }
+    if (this.constants != null && this.constants.size() > 0) {
+      pw.item("constants", constants);
+    }
     return pw;
   }
 

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

@@ -4123,7 +4123,7 @@ void testOrderByOnSortedTable2(String format) {
             "[deptno INTEGER NOT NULL, empid INTEGER NOT NULL, S REAL, FIVE INTEGER NOT NULL, M REAL, C BIGINT NOT NULL]")
         .explainContains(""
             + "EnumerableCalc(expr#0..7=[{inputs}], expr#8=[0:BIGINT], expr#9=[>($t4, $t8)], expr#10=[null:JavaType(class java.lang.Float)], expr#11=[CASE($t9, $t5, $t10)], expr#12=[5], deptno=[$t1], empid=[$t0], S=[$t11], FIVE=[$t12], M=[$t6], C=[$t7])\n"
-            + "  EnumerableWindow(window#0=[window(partition {1} order by [0] rows between $4 PRECEDING and CURRENT ROW aggs [COUNT($3), $SUM0($3), MIN($2), COUNT()])])\n"
+            + "  EnumerableWindow(window#0=[window(partition {1} order by [0] rows between $4 PRECEDING and CURRENT ROW aggs [COUNT($3), $SUM0($3), MIN($2), COUNT()])], constants=[[1]])\n"
             + "    EnumerableCalc(expr#0..4=[{inputs}], expr#5=[+($t3, $t0)], proj#0..1=[{exprs}], salary=[$t3], $3=[$t5])\n"
             + "      EnumerableTableScan(table=[[hr, emps]])\n")
         .returnsUnordered(

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

@@ -5892,6 +5892,20 @@ private HepProgram getTransitiveProgram() {
         .check();
   }
 
+  /** Test case for
+   * <a href="https://issues.apache.org/jira/browse/CALCITE-6632">[CALCITE-6632]
+   * Wrong optimization because window missing constants in digest</a>. */
+  @Test void testWindowMissingConstantInDigest() {
+    final String sql = "select sum(100) over (partition by deptno order by sal) as s\n"
+        + "from emp\n"
+        + "union all\n"
+        + "select sum(1000) over(partition by deptno order by sal) as s\n"
+        + "from emp\n";
+    sql(sql)
+        .withRule(CoreRules.PROJECT_TO_LOGICAL_PROJECT_AND_WINDOW)
+        .check();
+  }
+
   /** While it's probably valid relational algebra for a Project to contain
    * a RexOver inside a RexOver, ProjectMergeRule should not bring it about. */
   @Test void testProjectMergeShouldIgnoreOver() {

core/src/test/resources/org/apache/calcite/test/RelOptRulesTest.xml

@@ -4441,7 +4441,7 @@ ROWS BETWEEN 5 + 5 PRECEDING AND 1 PRECEDING) AS w_count from emp
     <Resource name="planBefore">
       <![CDATA[
 LogicalProject($0=[$1])
-  LogicalWindow(window#0=[window(order by [0] rows between $1 PRECEDING and $2 PRECEDING aggs [COUNT()])])
+  LogicalWindow(window#0=[window(order by [0] rows between $1 PRECEDING and $2 PRECEDING aggs [COUNT()])], constants=[[10, 1]])
     LogicalProject(EMPNO=[$0])
       LogicalTableScan(table=[[CATALOG, SALES, EMP]])
 ]]>
@@ -5328,7 +5328,7 @@ LogicalProject(EMPNO=[$0], DEPTNO=[$1], W_COUNT=[$2])
       <![CDATA[
 LogicalProject(EMPNO=[$0], DEPTNO=[$1], W_COUNT=[$2])
   LogicalFilter(condition=[IS NULL($2)])
-    LogicalWindow(window#0=[window(rows between $2 PRECEDING and $3 PRECEDING aggs [COUNT($0)])])
+    LogicalWindow(window#0=[window(rows between $2 PRECEDING and $3 PRECEDING aggs [COUNT($0)])], constants=[[10, 1]])
       LogicalProject(EMPNO=[$0], DEPTNO=[$7])
         LogicalTableScan(table=[[CATALOG, SALES, EMP]])
 ]]>
@@ -8409,7 +8409,7 @@ LogicalProject(EXPR$0=[CAST(/(CASE(>(COUNT($5) OVER (ORDER BY $0 ROWS 3 PRECEDIN
     <Resource name="planAfter">
       <![CDATA[
 LogicalProject(EXPR$0=[CAST(/(CASE(>($2, 0), $3, null:INTEGER), $2)):INTEGER])
-  LogicalWindow(window#0=[window(order by [0] rows between $2 PRECEDING and CURRENT ROW aggs [COUNT($1), $SUM0($1)])])
+  LogicalWindow(window#0=[window(order by [0] rows between $2 PRECEDING and CURRENT ROW aggs [COUNT($1), $SUM0($1)])], constants=[[3]])
     LogicalProject(EMPNO=[$0], SAL=[$5])
       LogicalTableScan(table=[[CATALOG, SALES, EMP]])
 ]]>
@@ -8509,7 +8509,7 @@ from (
     <Resource name="planAfter">
       <![CDATA[
 LogicalProject($0=[$2], $1=[$3])
-  LogicalWindow(window#0=[window(partition {1} order by [0] aggs [SUM($2), SUM($3)])])
+  LogicalWindow(window#0=[window(partition {1} order by [0] aggs [SUM($2), SUM($3)])], constants=[[100, 1000]])
     LogicalProject(SAL=[$5], DEPTNO=[$7])
       LogicalTableScan(table=[[CATALOG, SALES, EMP]])
 ]]>
@@ -10603,15 +10603,15 @@ where DEPTNO = 1]]>
 LogicalProject(NAME=[$0], DEPTNO=[$1], CNT=[$2], ALL_SUM=[$3])
   LogicalFilter(condition=[=($1, 1)])
     LogicalProject(NAME=[$1], DEPTNO=[$0], CNT=[$2], ALL_SUM=[$3])
-      LogicalWindow(window#0=[window(partition {0, 1} aggs [COUNT()])], window#1=[window(partition {0} aggs [SUM($2)])])
+      LogicalWindow(window#0=[window(partition {0, 1} aggs [COUNT()])], window#1=[window(partition {0} aggs [SUM($2)])], constants=[[1]])
         LogicalTableScan(table=[[CATALOG, SALES, DEPT]])
 ]]>
     </Resource>
     <Resource name="planAfter">
       <![CDATA[
 LogicalProject(NAME=[$1], DEPTNO=[$0], CNT=[$2], ALL_SUM=[$3])
   LogicalFilter(condition=[=($0, 1)])
-    LogicalWindow(window#0=[window(partition {0, 1} aggs [COUNT()])], window#1=[window(partition {0} aggs [SUM($2)])])
+    LogicalWindow(window#0=[window(partition {0, 1} aggs [COUNT()])], window#1=[window(partition {0} aggs [SUM($2)])], constants=[[1]])
       LogicalTableScan(table=[[CATALOG, SALES, DEPT]])
 ]]>
     </Resource>
@@ -13055,7 +13055,7 @@ from (
     <Resource name="planAfter">
       <![CDATA[
 LogicalProject($0=[$2], $1=[$3], $2=[$4])
-  LogicalWindow(window#0=[window(partition {1} range between UNBOUNDED PRECEDING and CURRENT ROW aggs [SUM($2)])], window#1=[window(order by [1] aggs [SUM($2)])], window#2=[window(partition {1} range between UNBOUNDED PRECEDING and CURRENT ROW aggs [SUM(5000)])])
+  LogicalWindow(window#0=[window(partition {1} range between UNBOUNDED PRECEDING and CURRENT ROW aggs [SUM($2)])], window#1=[window(order by [1] aggs [SUM($2)])], window#2=[window(partition {1} range between UNBOUNDED PRECEDING and CURRENT ROW aggs [SUM(5000)])], constants=[[100]])
     LogicalProject(SAL=[$5], DEPTNO=[$7])
       LogicalFilter(condition=[=($5, 5000)])
         LogicalTableScan(table=[[CATALOG, SALES, EMP]])
@@ -13088,7 +13088,7 @@ LogicalProject(COL1=[SUM(100) OVER (ORDER BY $7, $0 RANGE BETWEEN CURRENT ROW AN
     <Resource name="planAfter">
       <![CDATA[
 LogicalProject($0=[$3], $1=[$4])
-  LogicalWindow(window#0=[window(order by [2, 0] range between CURRENT ROW and UNBOUNDED FOLLOWING aggs [SUM($3)])], window#1=[window(partition {2} order by [2, 0] range between UNBOUNDED PRECEDING and UNBOUNDED FOLLOWING aggs [SUM($3)])])
+  LogicalWindow(window#0=[window(order by [2, 0] range between CURRENT ROW and UNBOUNDED FOLLOWING aggs [SUM($3)])], window#1=[window(partition {2} order by [2, 0] range between UNBOUNDED PRECEDING and UNBOUNDED FOLLOWING aggs [SUM($3)])], constants=[[100]])
     LogicalProject(EMPNO=[$0], SAL=[$5], DEPTNO=[$7])
       LogicalFilter(condition=[=($5, 5000)])
         LogicalTableScan(table=[[CATALOG, SALES, EMP]])
@@ -17232,6 +17232,38 @@ LogicalProject(EXPR$0=[$9], EXPR$1=[$9])
       <![CDATA[
 LogicalProject(EXPR$0=[COUNT() OVER (PARTITION BY $0 ORDER BY $0)], EXPR$1=[COUNT() OVER (PARTITION BY $0 ORDER BY $0)])
   LogicalTableScan(table=[[CATALOG, SALES, EMP]])
+]]>
+    </Resource>
+  </TestCase>
+  <TestCase name="testWindowMissingConstantInDigest">
+    <Resource name="sql">
+      <![CDATA[select sum(100) over (partition by deptno order by sal) as s
+from emp
+union all
+select sum(1000) over(partition by deptno order by sal) as s
+from emp
+]]>
+    </Resource>
+    <Resource name="planBefore">
+      <![CDATA[
+LogicalUnion(all=[true])
+  LogicalProject(S=[SUM(100) OVER (PARTITION BY $7 ORDER BY $5)])
+    LogicalTableScan(table=[[CATALOG, SALES, EMP]])
+  LogicalProject(S=[SUM(1000) OVER (PARTITION BY $7 ORDER BY $5)])
+    LogicalTableScan(table=[[CATALOG, SALES, EMP]])
+]]>
+    </Resource>
+    <Resource name="planAfter">
+      <![CDATA[
+LogicalUnion(all=[true])
+  LogicalProject($0=[$2])
+    LogicalWindow(window#0=[window(partition {1} order by [0] aggs [SUM($2)])], constants=[[100]])
+      LogicalProject(SAL=[$5], DEPTNO=[$7])
+        LogicalTableScan(table=[[CATALOG, SALES, EMP]])
+  LogicalProject($0=[$2])
+    LogicalWindow(window#0=[window(partition {1} order by [0] aggs [SUM($2)])], constants=[[1000]])
+      LogicalProject(SAL=[$5], DEPTNO=[$7])
+        LogicalTableScan(table=[[CATALOG, SALES, EMP]])
 ]]>
     </Resource>
   </TestCase>