Fix subtraction of timestamps

h2/src/main/org/h2/expression/IntervalOperation.java

@@ -5,6 +5,11 @@
  */
 package org.h2.expression;
 
+import static org.h2.util.DateTimeUtils.NANOS_PER_DAY;
+import static org.h2.util.DateTimeUtils.absoluteDayFromDateValue;
+import static org.h2.util.DateTimeUtils.dateAndTimeFromValue;
+import static org.h2.util.DateTimeUtils.dateTimeToValue;
+import static org.h2.util.DateTimeUtils.dateValueFromAbsoluteDay;
 import static org.h2.util.IntervalUtils.NANOS_PER_DAY_BI;
 
 import java.math.BigDecimal;
@@ -17,7 +22,6 @@ import org.h2.message.DbException;
 import org.h2.table.ColumnResolver;
 import org.h2.table.TableFilter;
 import org.h2.util.DateTimeFunctions;
-import org.h2.util.DateTimeUtils;
 import org.h2.util.IntervalUtils;
 import org.h2.value.DataType;
 import org.h2.value.Value;
@@ -73,6 +77,12 @@ public class IntervalOperation extends Expression {
     private Expression left, right;
     private int dataType;
 
+    private static BigInteger nanosFromValue(Value v) {
+        long[] a = dateAndTimeFromValue(v);
+        return BigInteger.valueOf(absoluteDayFromDateValue(a[0])).multiply(NANOS_PER_DAY_BI)
+                .add(BigInteger.valueOf(a[1]));
+    }
+
     public IntervalOperation(IntervalOpType opType, Expression left, Expression right) {
         this.opType = opType;
         this.left = left;
@@ -161,21 +171,15 @@ public class IntervalOperation extends Expression {
                 return ValueInterval.from(IntervalQualifier.HOUR_TO_SECOND, negative, diff / 3_600_000_000_000L,
                         diff % 3_600_000_000_000L);
             } else if (lType == Value.DATE && rType == Value.DATE) {
-                long diff = DateTimeUtils.absoluteDayFromDateValue(((ValueDate) l).getDateValue())
-                        - DateTimeUtils.absoluteDayFromDateValue(((ValueDate) r).getDateValue());
+                long diff = absoluteDayFromDateValue(((ValueDate) l).getDateValue())
+                        - absoluteDayFromDateValue(((ValueDate) r).getDateValue());
                 boolean negative = diff < 0;
                 if (negative) {
                     diff = -diff;
                 }
                 return ValueInterval.from(IntervalQualifier.DAY, negative, diff, 0L);
             } else {
-                long[] a = DateTimeUtils.dateAndTimeFromValue(l);
-                long[] b = DateTimeUtils.dateAndTimeFromValue(r);
-                BigInteger bi1 = BigInteger.valueOf(a[0]).multiply(NANOS_PER_DAY_BI)
-                        .add(BigInteger.valueOf(a[1]));
-                BigInteger bi2 = BigInteger.valueOf(b[0]).multiply(NANOS_PER_DAY_BI)
-                        .add(BigInteger.valueOf(b[1]));
-                BigInteger diff = bi1.subtract(bi2);
+                BigInteger diff = nanosFromValue(l).subtract(nanosFromValue(r));
                 if (lType == Value.TIMESTAMP_TZ || rType == Value.TIMESTAMP_TZ) {
                     l = l.convertTo(Value.TIMESTAMP_TZ);
                     r = r.convertTo(Value.TIMESTAMP_TZ);
@@ -214,14 +218,13 @@ public class IntervalOperation extends Expression {
             } else {
                 BigInteger a2 = IntervalUtils.intervalToAbsolute((ValueInterval) r);
                 if (lType == Value.DATE) {
-                    BigInteger a1 = BigInteger
-                            .valueOf(DateTimeUtils.absoluteDayFromDateValue(((ValueDate) l).getDateValue()));
+                    BigInteger a1 = BigInteger.valueOf(absoluteDayFromDateValue(((ValueDate) l).getDateValue()));
                     a2 = a2.divide(NANOS_PER_DAY_BI);
                     BigInteger n = opType == IntervalOpType.DATETIME_PLUS_INTERVAL ? a1.add(a2) : a1.subtract(a2);
-                    return ValueDate.fromDateValue(DateTimeUtils.dateValueFromAbsoluteDay(n.longValue()));
+                    return ValueDate.fromDateValue(dateValueFromAbsoluteDay(n.longValue()));
                 } else {
-                    long[] a = DateTimeUtils.dateAndTimeFromValue(l);
-                    long absoluteDay = DateTimeUtils.absoluteDayFromDateValue(a[0]);
+                    long[] a = dateAndTimeFromValue(l);
+                    long absoluteDay = absoluteDayFromDateValue(a[0]);
                     long timeNanos = a[1];
                     BigInteger[] dr = a2.divideAndRemainder(NANOS_PER_DAY_BI);
                     if (opType == IntervalOpType.DATETIME_PLUS_INTERVAL) {
@@ -231,15 +234,14 @@ public class IntervalOperation extends Expression {
                         absoluteDay -= dr[0].longValue();
                         timeNanos -= dr[1].longValue();
                     }
-                    if (timeNanos >= DateTimeUtils.NANOS_PER_DAY) {
-                        timeNanos -= DateTimeUtils.NANOS_PER_DAY;
+                    if (timeNanos >= NANOS_PER_DAY) {
+                        timeNanos -= NANOS_PER_DAY;
                         absoluteDay++;
                     } else if (timeNanos < 0) {
-                        timeNanos += DateTimeUtils.NANOS_PER_DAY;
+                        timeNanos += NANOS_PER_DAY;
                         absoluteDay--;
                     }
-                    return DateTimeUtils.dateTimeToValue(l, DateTimeUtils.dateValueFromAbsoluteDay(absoluteDay),
-                            timeNanos, false);
+                    return dateTimeToValue(l, dateValueFromAbsoluteDay(absoluteDay), timeNanos, false);
                 }
             }
         }

h2/src/test/org/h2/test/scripts/datatypes/interval.sql

@@ -775,3 +775,12 @@ DROP TABLE TEST;
 
 CREATE TABLE TEST(I INTERVAL HOUR TO SECOND(10));
 > exception INVALID_VALUE_SCALE_PRECISION
+
+SELECT TIMESTAMP '2018-09-10 23:30:00' - TIMESTAMP '2014-09-11 23:30:00';
+>> INTERVAL '1460 00:00:00' DAY TO SECOND
+
+SELECT TIMESTAMP WITH TIME ZONE '2014-09-11 23:30:00Z' - TIMESTAMP WITH TIME ZONE '2018-09-10 23:30:00Z';
+>> INTERVAL '-1460 00:00:00' DAY TO SECOND
+
+SELECT DATE '2018-09-10' - DATE '2014-09-11';
+>> INTERVAL '1460' DAY