Fix return type of PERCENTILE_CONT and MEDIAN

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

@@ -5,6 +5,7 @@
  */
 package org.h2.expression.aggregate;
 
+import java.math.BigDecimal;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Comparator;
@@ -322,8 +323,8 @@ public class Aggregate extends AbstractAggregate {
             if (v == ValueNull.INSTANCE) {
                 return ValueNull.INSTANCE;
             }
-            double arg = v.getDouble();
-            if (arg >= 0d && arg <= 1d) {
+            BigDecimal arg = v.getBigDecimal();
+            if (arg.signum() >= 0 && arg.compareTo(BigDecimal.ONE) <= 0) {
                 return Percentile.getFromIndex(session, orderByList.get(0).expression, type.getValueType(),
                         orderByList, arg, aggregateType == AggregateType.PERCENTILE_CONT);
             } else {
@@ -332,7 +333,7 @@ public class Aggregate extends AbstractAggregate {
             }
         }
         case MEDIAN:
-            return Percentile.getFromIndex(session, on, type.getValueType(), orderByList, 0.5d, true);
+            return Percentile.getFromIndex(session, on, type.getValueType(), orderByList, Percentile.HALF, true);
         case ENVELOPE:
             return ((MVSpatialIndex) AggregateDataEnvelope.getGeometryColumnIndex(on)).getBounds(session);
         default:
@@ -402,8 +403,8 @@ public class Aggregate extends AbstractAggregate {
             if (v == ValueNull.INSTANCE) {
                 return ValueNull.INSTANCE;
             }
-            double arg = v.getDouble();
-            if (arg >= 0d && arg <= 1d) {
+            BigDecimal arg = v.getBigDecimal();
+            if (arg.signum() >= 0 && arg.compareTo(BigDecimal.ONE) <= 0) {
                 return Percentile.getValue(session.getDatabase(), array, type.getValueType(), orderByList, arg,
                         aggregateType == AggregateType.PERCENTILE_CONT);
             } else {
@@ -416,7 +417,8 @@ public class Aggregate extends AbstractAggregate {
             if (array == null) {
                 return ValueNull.INSTANCE;
             }
-            return Percentile.getValue(session.getDatabase(), array, type.getValueType(), orderByList, 0.5d, true);
+            return Percentile.getValue(session.getDatabase(), array, type.getValueType(), orderByList, Percentile.HALF,
+                    true);
         }
         case MODE:
             return getMode(session, data);
@@ -589,9 +591,23 @@ public class Aggregate extends AbstractAggregate {
             break;
         case MIN:
         case MAX:
-        case MEDIAN:
             break;
         case PERCENTILE_CONT:
+            type = orderByList.get(0).expression.getType();
+            //$FALL-THROUGH$
+        case MEDIAN:
+            switch (type.getValueType()) {
+            case Value.BYTE:
+            case Value.SHORT:
+            case Value.INT:
+            case Value.LONG:
+            case Value.DECIMAL:
+            case Value.DOUBLE:
+            case Value.FLOAT:
+                type = TypeInfo.TYPE_DECIMAL_DEFAULT;
+                break;
+            }
+            break;
         case PERCENTILE_DISC:
         case MODE:
             type = orderByList.get(0).expression.getType();

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

@@ -32,11 +32,7 @@ import org.h2.value.CompareMode;
 import org.h2.value.Value;
 import org.h2.value.ValueDate;
 import org.h2.value.ValueDecimal;
-import org.h2.value.ValueDouble;
-import org.h2.value.ValueFloat;
-import org.h2.value.ValueInt;
 import org.h2.value.ValueInterval;
-import org.h2.value.ValueLong;
 import org.h2.value.ValueNull;
 import org.h2.value.ValueTime;
 import org.h2.value.ValueTimestamp;
@@ -47,6 +43,11 @@ import org.h2.value.ValueTimestampTimeZone;
  */
 final class Percentile {
 
+    /**
+     * BigDecimal value of 0.5.
+     */
+    static final BigDecimal HALF = BigDecimal.valueOf(0.5d);
+
     private static boolean isNullsLast(Index index) {
         IndexColumn ic = index.getIndexColumns()[0];
         int sortType = ic.sortType;
@@ -106,22 +107,22 @@ final class Percentile {
      * @return the result
      */
     static Value getValue(Database database, Value[] array, int dataType, ArrayList<SelectOrderBy> orderByList,
-            double percentile, boolean interpolate) {
+            BigDecimal percentile, boolean interpolate) {
         final CompareMode compareMode = database.getCompareMode();
         Arrays.sort(array, compareMode);
         int count = array.length;
         boolean reverseIndex = orderByList != null && (orderByList.get(0).sortType & SortOrder.DESCENDING) != 0;
-        double fpRow = (count - 1) * percentile;
-        int rowIdx1 = (int) fpRow;
-        double factor = fpRow - rowIdx1;
+        BigDecimal fpRow = BigDecimal.valueOf(count - 1).multiply(percentile);
+        int rowIdx1 = fpRow.intValue();
+        BigDecimal factor = fpRow.subtract(BigDecimal.valueOf(rowIdx1));
         int rowIdx2;
-        if (factor == 0d) {
+        if (factor.signum() == 0) {
             interpolate = false;
             rowIdx2 = rowIdx1;
         } else {
             rowIdx2 = rowIdx1 + 1;
             if (!interpolate) {
-                if (factor > 0.5d) {
+                if (factor.compareTo(HALF) > 0) {
                     rowIdx1 = rowIdx2;
                 } else {
                     rowIdx2 = rowIdx1;
@@ -151,7 +152,7 @@ final class Percentile {
      * @return the result
      */
     static Value getFromIndex(Session session, Expression expression, int dataType,
-            ArrayList<SelectOrderBy> orderByList, double percentile, boolean interpolate) {
+            ArrayList<SelectOrderBy> orderByList, BigDecimal percentile, boolean interpolate) {
         Index index = getColumnIndex(expression);
         long count = index.getRowCount(session);
         if (count == 0) {
@@ -199,17 +200,17 @@ final class Percentile {
         }
         boolean reverseIndex = (orderByList != null ? orderByList.get(0).sortType & SortOrder.DESCENDING : 0)
                 != (index.getIndexColumns()[0].sortType & SortOrder.DESCENDING);
-        double fpRow = (count - 1) * percentile;
-        long rowIdx1 = (long) fpRow;
-        double factor = fpRow - rowIdx1;
+        BigDecimal fpRow = BigDecimal.valueOf(count - 1).multiply(percentile);
+        long rowIdx1 = fpRow.longValue();
+        BigDecimal factor = fpRow.subtract(BigDecimal.valueOf(rowIdx1));
         long rowIdx2;
-        if (factor == 0d) {
+        if (factor.signum() == 0) {
             interpolate = false;
             rowIdx2 = rowIdx1;
         } else {
             rowIdx2 = rowIdx1 + 1;
             if (!interpolate) {
-                if (factor > 0.5d) {
+                if (factor.compareTo(HALF) > 0) {
                     rowIdx1 = rowIdx2;
                 } else {
                     rowIdx2 = rowIdx1;
@@ -246,10 +247,10 @@ final class Percentile {
             }
             return interpolate(v, v2, factor, dataType, database.getMode(), database.getCompareMode());
         }
-        return v;
+        return v.convertTo(dataType);
     }
 
-    private static Value interpolate(Value v0, Value v1, double factor, int dataType, Mode databaseMode,
+    private static Value interpolate(Value v0, Value v1, BigDecimal factor, int dataType, Mode databaseMode,
             CompareMode compareMode) {
         if (v0.compareTo(v1, databaseMode, compareMode) == 0) {
             return v0.convertTo(dataType);
@@ -258,21 +259,18 @@ final class Percentile {
         case Value.BYTE:
         case Value.SHORT:
         case Value.INT:
-            return ValueInt.get((int) (v0.getInt() * (1 - factor) + v1.getInt() * factor)).convertTo(dataType);
+            return ValueDecimal.get(
+                    interpolateDecimal(BigDecimal.valueOf(v0.getInt()), BigDecimal.valueOf(v1.getInt()), factor));
         case Value.LONG:
-            return ValueLong
-                    .get(interpolateDecimal(BigDecimal.valueOf(v0.getLong()), BigDecimal.valueOf(v1.getLong()), factor)
-                            .longValue());
+            return ValueDecimal.get(
+                    interpolateDecimal(BigDecimal.valueOf(v0.getLong()), BigDecimal.valueOf(v1.getLong()), factor));
         case Value.DECIMAL:
             return ValueDecimal.get(interpolateDecimal(v0.getBigDecimal(), v1.getBigDecimal(), factor));
         case Value.FLOAT:
-            return ValueFloat.get(
-                    interpolateDecimal(BigDecimal.valueOf(v0.getFloat()), BigDecimal.valueOf(v1.getFloat()), factor)
-                            .floatValue());
         case Value.DOUBLE:
-            return ValueDouble.get(
-                    interpolateDecimal(BigDecimal.valueOf(v0.getDouble()), BigDecimal.valueOf(v1.getDouble()), factor)
-                            .doubleValue());
+            return ValueDecimal.get(
+                    interpolateDecimal(
+                            BigDecimal.valueOf(v0.getDouble()), BigDecimal.valueOf(v1.getDouble()), factor));
         case Value.TIME: {
             ValueTime t0 = (ValueTime) v0.convertTo(Value.TIME), t1 = (ValueTime) v1.convertTo(Value.TIME);
             BigDecimal n0 = BigDecimal.valueOf(t0.getNanos());
@@ -307,12 +305,15 @@ final class Percentile {
                     ts1 = (ValueTimestampTimeZone) v1.convertTo(Value.TIMESTAMP_TZ);
             BigDecimal a0 = timestampToDecimal(ts0.getDateValue(), ts0.getTimeNanos());
             BigDecimal a1 = timestampToDecimal(ts1.getDateValue(), ts1.getTimeNanos());
-            double offset = ts0.getTimeZoneOffsetMins() * (1 - factor) + ts1.getTimeZoneOffsetMins() * factor;
-            short sOffset = (short) offset;
+            BigDecimal offset = BigDecimal.valueOf(ts0.getTimeZoneOffsetMins())
+                    .multiply(BigDecimal.ONE.subtract(factor))
+                    .add(BigDecimal.valueOf(ts1.getTimeZoneOffsetMins()).multiply(factor));
+            short shortOffset = offset.shortValue();
+            BigDecimal shortOffsetBD = BigDecimal.valueOf(shortOffset);
             BigDecimal bd = interpolateDecimal(a0, a1, factor);
-            if (offset != sOffset) {
-                bd = bd.add(BigDecimal.valueOf(offset - sOffset)
-                        .multiply(BigDecimal.valueOf(DateTimeUtils.NANOS_PER_MINUTE)));
+            if (offset.compareTo(shortOffsetBD) != 0) {
+                bd = bd.add(
+                        offset.subtract(shortOffsetBD).multiply(BigDecimal.valueOf(DateTimeUtils.NANOS_PER_MINUTE)));
             }
             BigInteger[] dr = bd.toBigInteger().divideAndRemainder(IntervalUtils.NANOS_PER_DAY_BI);
             long absoluteDay = dr[0].longValue();
@@ -322,7 +323,7 @@ final class Percentile {
                 absoluteDay--;
             }
             return ValueTimestampTimeZone.fromDateValueAndNanos(DateTimeUtils.dateValueFromAbsoluteDay(absoluteDay),
-                    timeNanos, sOffset);
+                    timeNanos, shortOffset);
         }
         case Value.INTERVAL_YEAR:
         case Value.INTERVAL_MONTH:
@@ -343,7 +344,7 @@ final class Percentile {
                                     .toBigInteger());
         default:
             // Use the same rules as PERCENTILE_DISC
-            return (factor > 0.5d ? v1 : v0).convertTo(dataType);
+            return (factor.compareTo(HALF) > 0 ? v1 : v0).convertTo(dataType);
         }
     }
 
@@ -352,8 +353,8 @@ final class Percentile {
                 .multiply(IntervalUtils.NANOS_PER_DAY_BI).add(BigInteger.valueOf(timeNanos)));
     }
 
-    private static BigDecimal interpolateDecimal(BigDecimal d0, BigDecimal d1, double factor) {
-        return d0.multiply(BigDecimal.valueOf(1 - factor)).add(d1.multiply(BigDecimal.valueOf(factor)));
+    private static BigDecimal interpolateDecimal(BigDecimal d0, BigDecimal d1, BigDecimal factor) {
+        return d0.multiply(BigDecimal.ONE.subtract(factor)).add(d1.multiply(factor));
     }
 
     private Percentile() {

h2/src/main/org/h2/value/ValueFloat.java

@@ -130,6 +130,11 @@ public class ValueFloat extends Value {
         return value;
     }
 
+    @Override
+    public double getDouble() {
+        return value;
+    }
+
     @Override
     public String getString() {
         return Float.toString(value);

h2/src/test/org/h2/test/scripts/functions/aggregate/percentile.sql

@@ -35,7 +35,7 @@ select
 > rows: 1
 
 select median(distinct v) from test;
->> 15
+>> 15.0
 
 insert into test values (10);
 > update count: 1
@@ -45,8 +45,8 @@ select
     percentile_disc(0.5) within group (order by v desc) d50d,
     median(v) m from test;
 > D50A D50D M
-> ---- ---- --
-> 10   20   15
+> ---- ---- ----
+> 10   20   15.0
 > rows: 1
 
 drop table test;
@@ -84,7 +84,7 @@ select
 > rows: 1
 
 select median(distinct v) from test;
->> 15
+>> 15.0
 
 insert into test values (10);
 > update count: 1
@@ -94,8 +94,8 @@ select
     percentile_disc(0.5) within group (order by v desc) d50d,
     median(v) m from test;
 > D50A D50D M
-> ---- ---- --
-> 10   20   15
+> ---- ---- ----
+> 10   20   15.0
 > rows: 1
 
 drop table test;
@@ -133,7 +133,7 @@ select
 > rows: 1
 
 select median(distinct v) from test;
->> 15
+>> 15.0
 
 insert into test values (10);
 > update count: 1
@@ -143,8 +143,8 @@ select
     percentile_disc(0.5) within group (order by v desc) d50d,
     median(v) m from test;
 > D50A D50D M
-> ---- ---- --
-> 10   20   15
+> ---- ---- ----
+> 10   20   15.0
 > rows: 1
 
 drop table test;
@@ -182,7 +182,7 @@ select
 > rows: 1
 
 select median(distinct v) from test;
->> 15
+>> 15.0
 
 insert into test values (10);
 > update count: 1
@@ -192,8 +192,8 @@ select
     percentile_disc(0.5) within group (order by v desc) d50d,
     median(v) m from test;
 > D50A D50D M
-> ---- ---- --
-> 10   20   15
+> ---- ---- ----
+> 10   20   15.0
 > rows: 1
 
 drop table test;
@@ -231,7 +231,7 @@ select
 > rows: 1
 
 select median(distinct v) from test;
->> 15
+>> 15.0
 
 insert into test values (10);
 > update count: 1
@@ -241,8 +241,8 @@ select
     percentile_disc(0.5) within group (order by v desc) d50d,
     median(v) m from test;
 > D50A D50D M
-> ---- ---- --
-> 10   20   15
+> ---- ---- ----
+> 10   20   15.0
 > rows: 1
 
 drop table test;
@@ -280,7 +280,7 @@ select
 > rows: 1
 
 select median(distinct v) from test;
->> 15
+>> 15.0
 
 insert into test values (10);
 > update count: 1
@@ -290,8 +290,8 @@ select
     percentile_disc(0.5) within group (order by v desc) d50d,
     median(v) m from test;
 > D50A D50D M
-> ---- ---- --
-> 10   20   15
+> ---- ---- ----
+> 10   20   15.0
 > rows: 1
 
 drop table test;
@@ -313,13 +313,13 @@ select median(v) from test;
 >> 20
 
 select median(distinct v) from test;
->> 15
+>> 15.0
 
 insert into test values (10);
 > update count: 1
 
 select median(v) from test;
->> 15
+>> 15.0
 
 drop table test;
 > ok
@@ -340,13 +340,13 @@ select median(v) from test;
 >> 20
 
 select median(distinct v) from test;
->> 15
+>> 15.0
 
 insert into test values (10);
 > update count: 1
 
 select median(v) from test;
->> 15
+>> 15.0
 
 drop table test;
 > ok
@@ -367,13 +367,13 @@ select median(v) from test;
 >> 20
 
 select median(distinct v) from test;
->> 15
+>> 15.0
 
 insert into test values (10);
 > update count: 1
 
 select median(v) from test;
->> 15
+>> 15.0
 
 drop table test;
 > ok
@@ -394,13 +394,13 @@ select median(v) from test;
 >> 20
 
 select median(distinct v) from test;
->> 15
+>> 15.0
 
 insert into test values (10);
 > update count: 1
 
 select median(v) from test;
->> 15
+>> 15.0
 
 drop table test;
 > ok
@@ -421,13 +421,13 @@ select median(v) from test;
 >> 2.0
 
 select median(distinct v) from test;
->> 1.5
+>> 1.50
 
 insert into test values (1);
 > update count: 1
 
 select median(v) from test;
->> 1.5
+>> 1.50
 
 drop table test;
 > ok
@@ -448,13 +448,13 @@ select median(v) from test;
 >> 2.0
 
 select median(distinct v) from test;
->> 1.5
+>> 1.50
 
 insert into test values (1);
 > update count: 1
 
 select median(v) from test;
->> 1.5
+>> 1.50
 
 drop table test;
 > ok
@@ -650,7 +650,7 @@ insert into test values ('Group 2A', 10), ('Group 2A', 10), ('Group 2A', 20),
 select name, median(value) from test group by name order by name;
 > NAME     MEDIAN(VALUE)
 > -------- -------------
-> Group 1X 45
+> Group 1X 45.0
 > Group 2A 10
 > Group 3B null
 > rows (ordered): 3
@@ -707,7 +707,7 @@ insert into test values (10), (20);
 > update count: 2
 
 select median(v) from test;
->> 15
+>> 15.0
 
 insert into test values (20), (10), (20);
 > update count: 3
@@ -729,7 +729,7 @@ insert into test values (10), (20), (30), (40), (50), (60), (70), (80), (90), (1
 select median(v), median(v) filter (where v >= 40) from test where v <= 100;
 > MEDIAN(V) MEDIAN(V) FILTER (WHERE (V >= 40))
 > --------- ----------------------------------
-> 55        70
+> 55.0      70
 > rows: 1
 
 create index test_idx on test(v);
@@ -738,13 +738,13 @@ create index test_idx on test(v);
 select median(v), median(v) filter (where v >= 40) from test where v <= 100;
 > MEDIAN(V) MEDIAN(V) FILTER (WHERE (V >= 40))
 > --------- ----------------------------------
-> 55        70
+> 55.0      70
 > rows: 1
 
 select median(v), median(v) filter (where v >= 40) from test;
 > MEDIAN(V) MEDIAN(V) FILTER (WHERE (V >= 40))
 > --------- ----------------------------------
-> 65        80
+> 65.0      80
 > rows: 1
 
 drop table test;
@@ -774,7 +774,7 @@ select dept, median(amount) filter (where amount >= 20) from test group by dept
 > ------ --------------------------------------------
 > First  30
 > Second 22
-> Third  160
+> Third  160.0
 > rows (ordered): 3
 
 select dept, median(amount) filter (where amount >= 20) from test
@@ -782,7 +782,7 @@ select dept, median(amount) filter (where amount >= 20) from test
 > DEPT   MEDIAN(AMOUNT) FILTER (WHERE (AMOUNT >= 20))
 > ------ --------------------------------------------
 > First  30
-> Second 21
+> Second 21.0
 > Third  150
 > rows (ordered): 3
 
@@ -804,10 +804,10 @@ select
     percentile_cont(0.95) within group (order by v) c95a,
     percentile_cont(0.95) within group (order by v desc) c95d,
     g from test group by g;
-> C05A C05D C50 C50D C95A C95D G
-> ---- ---- --- ---- ---- ---- -
-> 1    9    5   5    9    1    1
-> 11   89   25  25   89   11   2
+> C05A  C05D  C50  C50D C95A  C95D  G
+> ----- ----- ---- ---- ----- ----- -
+> 1.45  9.55  5.5  5.5  9.55  1.45  1
+> 11.50 89.50 25.0 25.0 89.50 11.50 2
 > rows: 2
 
 select