Merge pull request #1705 from katzyn/aggregate

Fix GROUP_CONCAT with variable separator

h2/src/docsrc/help/help.csv

@@ -3545,6 +3545,7 @@ GROUP_CONCAT ( [ DISTINCT|ALL ] string
 [FILTER (WHERE expression)] [OVER windowNameOrSpecification]
 ","
 Concatenates strings with a separator.
+Separator must be the same for all rows in the same group.
 The default separator is a ',' (without space).
 This method returns a string.
 If no rows are selected, the result is NULL.

h2/src/main/org/h2/command/Parser.java

@@ -3041,43 +3041,50 @@ public class Parser {
         switch (aggregateType) {
         case COUNT:
             if (readIf(ASTERISK)) {
-                r = new Aggregate(AggregateType.COUNT_ALL, null, currentSelect, false);
+                r = new Aggregate(AggregateType.COUNT_ALL, new Expression[0], currentSelect, false);
             } else {
                 boolean distinct = readDistinctAgg();
                 Expression on = readExpression();
                 if (on instanceof Wildcard && !distinct) {
                     // PostgreSQL compatibility: count(t.*)
-                    r = new Aggregate(AggregateType.COUNT_ALL, null, currentSelect, false);
+                    r = new Aggregate(AggregateType.COUNT_ALL, new Expression[0], currentSelect, false);
                 } else {
-                    r = new Aggregate(AggregateType.COUNT, on, currentSelect, distinct);
+                    r = new Aggregate(AggregateType.COUNT, new Expression[] { on }, currentSelect, distinct);
                 }
             }
             break;
         case GROUP_CONCAT: {
             boolean distinct = readDistinctAgg();
-            r = new Aggregate(AggregateType.GROUP_CONCAT, readExpression(), currentSelect, distinct);
+            Expression arg = readExpression(), separator = null;
+            ArrayList<SelectOrderBy> orderByList = null;
             if (equalsToken("STRING_AGG", aggregateName)) {
                 // PostgreSQL compatibility: string_agg(expression, delimiter)
                 read(COMMA);
-                r.setGroupConcatSeparator(readExpression());
+                separator = readExpression();
                 if (readIf(ORDER)) {
                     read("BY");
-                    r.setOrderByList(parseSimpleOrderList());
+                    orderByList = parseSimpleOrderList();
                 }
             } else {
                 if (readIf(ORDER)) {
                     read("BY");
-                    r.setOrderByList(parseSimpleOrderList());
+                    orderByList = parseSimpleOrderList();
                 }
                 if (readIf("SEPARATOR")) {
-                    r.setGroupConcatSeparator(readExpression());
+                    separator = readExpression();
+                }
             }
+            r = new Aggregate(AggregateType.GROUP_CONCAT,
+                    separator == null ? new Expression[] { arg } : new Expression[] { arg, separator },
+                            currentSelect, distinct);
+            if (orderByList != null) {
+                r.setOrderByList(orderByList);
             }
             break;
         }
         case ARRAY_AGG: {
             boolean distinct = readDistinctAgg();
-            r = new Aggregate(AggregateType.ARRAY_AGG, readExpression(), currentSelect, distinct);
+            r = new Aggregate(AggregateType.ARRAY_AGG, new Expression[] { readExpression() }, currentSelect, distinct);
             if (readIf(ORDER)) {
                 read("BY");
                 r.setOrderByList(parseSimpleOrderList());
@@ -3088,15 +3095,15 @@ public class Parser {
         case PERCENTILE_DISC: {
             Expression num = readExpression();
             read(CLOSE_PAREN);
-            r = readWithinGroup(aggregateType, num);
+            r = readWithinGroup(aggregateType, new Expression[] { num });
             break;
         }
         case MODE: {
             if (readIf(CLOSE_PAREN)) {
-                r = readWithinGroup(AggregateType.MODE, null);
+                r = readWithinGroup(AggregateType.MODE, new Expression[0]);
             } else {
                 Expression expr = readExpression();
-                r = new Aggregate(aggregateType, null, currentSelect, false);
+                r = new Aggregate(aggregateType, new Expression[0], currentSelect, false);
                 if (readIf(ORDER)) {
                     read("BY");
                     Expression expr2 = readExpression();
@@ -3114,7 +3121,7 @@ public class Parser {
         }
         default:
             boolean distinct = readDistinctAgg();
-            r = new Aggregate(aggregateType, readExpression(), currentSelect, distinct);
+            r = new Aggregate(aggregateType, new Expression[] { readExpression() }, currentSelect, distinct);
             break;
         }
         read(CLOSE_PAREN);
@@ -3122,7 +3129,7 @@ public class Parser {
         return r;
     }
 
-    private Aggregate readWithinGroup(AggregateType aggregateType, Expression argument) {
+    private Aggregate readWithinGroup(AggregateType aggregateType, Expression[] args) {
         Aggregate r;
         read("WITHIN");
         read(GROUP);
@@ -3130,7 +3137,7 @@ public class Parser {
         read(ORDER);
         read("BY");
         Expression expr = readExpression();
-        r = new Aggregate(aggregateType, argument, currentSelect, false);
+        r = new Aggregate(aggregateType, args, currentSelect, false);
         readAggregateOrder(r, expr, true);
         return r;
     }

h2/src/main/org/h2/expression/aggregate/AbstractAggregate.java

@@ -22,6 +22,7 @@ import org.h2.expression.analysis.WindowFrameExclusion;
 import org.h2.expression.analysis.WindowFrameUnits;
 import org.h2.table.ColumnResolver;
 import org.h2.table.TableFilter;
+import org.h2.value.TypeInfo;
 import org.h2.value.Value;
 
 /**
@@ -34,13 +35,24 @@ public abstract class AbstractAggregate extends DataAnalysisOperation {
      */
     protected final boolean distinct;
 
+    /**
+     * The arguments.
+     */
+    protected final Expression[] args;
+
     /**
      * FILTER condition for aggregate
      */
     protected Expression filterCondition;
 
-    AbstractAggregate(Select select, boolean distinct) {
+    /**
+     * The type of the result.
+     */
+    protected TypeInfo type;
+
+    AbstractAggregate(Select select, Expression[] args, boolean distinct) {
         super(select);
+        this.args = args;
         this.distinct = distinct;
     }
 
@@ -59,8 +71,16 @@ public abstract class AbstractAggregate extends DataAnalysisOperation {
         this.filterCondition = filterCondition;
     }
 
+    @Override
+    public TypeInfo getType() {
+        return type;
+    }
+
     @Override
     public void mapColumnsAnalysis(ColumnResolver resolver, int level, int innerState) {
+        for (Expression arg : args) {
+            arg.mapColumns(resolver, level, innerState);
+        }
         if (filterCondition != null) {
             filterCondition.mapColumns(resolver, level, innerState);
         }
@@ -69,6 +89,9 @@ public abstract class AbstractAggregate extends DataAnalysisOperation {
 
     @Override
     public Expression optimize(Session session) {
+        for (int i = 0; i < args.length; i++) {
+            args[i] = args[i].optimize(session);
+        }
         if (filterCondition != null) {
             filterCondition = filterCondition.optimize(session);
         }
@@ -77,6 +100,9 @@ public abstract class AbstractAggregate extends DataAnalysisOperation {
 
     @Override
     public void setEvaluatable(TableFilter tableFilter, boolean b) {
+        for (Expression arg : args) {
+            arg.setEvaluatable(tableFilter, b);
+        }
         if (filterCondition != null) {
             filterCondition.setEvaluatable(tableFilter, b);
         }

h2/src/main/org/h2/expression/aggregate/JavaAggregate.java

@@ -15,8 +15,6 @@ import org.h2.engine.UserAggregate;
 import org.h2.expression.Expression;
 import org.h2.expression.ExpressionVisitor;
 import org.h2.message.DbException;
-import org.h2.table.ColumnResolver;
-import org.h2.table.TableFilter;
 import org.h2.value.DataType;
 import org.h2.value.TypeInfo;
 import org.h2.value.Value;
@@ -30,16 +28,13 @@ import org.h2.value.ValueRow;
 public class JavaAggregate extends AbstractAggregate {
 
     private final UserAggregate userAggregate;
-    private final Expression[] args;
     private int[] argTypes;
-    private TypeInfo type;
     private int dataType;
     private Connection userConnection;
 
     public JavaAggregate(UserAggregate userAggregate, Expression[] args, Select select, boolean distinct) {
-        super(select, distinct);
+        super(select, args, distinct);
         this.userAggregate = userAggregate;
-        this.args = args;
     }
 
     @Override
@@ -62,11 +57,6 @@ public class JavaAggregate extends AbstractAggregate {
         return appendTailConditions(builder);
     }
 
-    @Override
-    public TypeInfo getType() {
-        return type;
-    }
-
     @Override
     public boolean isEverything(ExpressionVisitor visitor) {
         if (!super.isEverything(visitor)) {
@@ -92,14 +82,6 @@ public class JavaAggregate extends AbstractAggregate {
         return filterCondition == null || filterCondition.isEverything(visitor);
     }
 
-    @Override
-    public void mapColumnsAnalysis(ColumnResolver resolver, int level, int innerState) {
-        for (Expression arg : args) {
-            arg.mapColumns(resolver, level, innerState);
-        }
-        super.mapColumnsAnalysis(resolver, level, innerState);
-    }
-
     @Override
     public Expression optimize(Session session) {
         super.optimize(session);
@@ -107,9 +89,7 @@ public class JavaAggregate extends AbstractAggregate {
         int len = args.length;
         argTypes = new int[len];
         for (int i = 0; i < len; i++) {
-            Expression expr = args[i];
-            args[i] = expr.optimize(session);
-            int type = expr.getType().getValueType();
+            int type = args[i].getType().getValueType();
             argTypes[i] = type;
         }
         try {
@@ -122,14 +102,6 @@ public class JavaAggregate extends AbstractAggregate {
         return this;
     }
 
-    @Override
-    public void setEvaluatable(TableFilter tableFilter, boolean b) {
-        for (Expression e : args) {
-            e.setEvaluatable(tableFilter, b);
-        }
-        super.setEvaluatable(tableFilter, b);
-    }
-
     private Aggregate getInstance() {
         Aggregate agg = userAggregate.getInstance();
         try {

h2/src/test/org/h2/test/scripts/functions/aggregate/group-concat.sql

@@ -67,3 +67,32 @@ select group_concat(distinct v order by v desc) from test;
 
 drop table test;
 > ok
+
+create table test(g varchar, v int) as values ('-', 1), ('-', 2), ('-', 3), ('|', 4), ('|', 5), ('|', 6), ('*', null);
+> ok
+
+select g, group_concat(v separator g) from test group by g;
+> G GROUP_CONCAT(V SEPARATOR G)
+> - ---------------------------
+> * null
+> - 1-2-3
+> | 4|5|6
+> rows: 3
+
+select g, group_concat(v separator g) over (partition by g) from test order by v;
+> G GROUP_CONCAT(V SEPARATOR G) OVER (PARTITION BY G)
+> - -------------------------------------------------
+> * null
+> - 1-2-3
+> - 1-2-3
+> - 1-2-3
+> | 4|5|6
+> | 4|5|6
+> | 4|5|6
+> rows (ordered): 7
+
+select g, group_concat(v separator v) from test group by g;
+> exception INVALID_VALUE_2
+
+drop table test;
+> ok