The double or float value -0.0 is now distinct from 0.0 (as in Java).

h2/src/main/org/h2/res/help.csv

@@ -479,7 +479,7 @@ condition [ { AND condition } [...] ]
 ","
 Value or condition."
 "Other Grammar","Array","
-( expression [,...] )
+( [ expression, [ expression [,...] ] ] )
 ","
 An array of values."
 "Other Grammar","Boolean","
@@ -576,7 +576,7 @@ A string starts and ends with two dollar signs."
 "Other Grammar","Double","
 [ + | - ] { { number [ . number ] } | { . number } } [ E [ + | - ] expNumber [...] ] ]
 ","
-The limitations are the same as for the Java data type Double."
+A floating point number with high precision."
 "Other Grammar","Expression","
 andCondition [ { OR andCondition } [...] ]
 ","
@@ -716,23 +716,23 @@ Data type with fixed precision and scale."
 "Data Types","DOUBLE Type","
 { DOUBLE [ PRECISION ] | FLOAT | FLOAT4 | FLOAT8 }
 ","
-Floating point number."
+A floating point number."
 "Data Types","REAL Type","
 REAL
 ","
-Single precision floating point number."
+A single precision floating point number."
 "Data Types","TIME Type","
 TIME
 ","
-The format is hh:mm:ss."
+The time data type."
 "Data Types","DATE Type","
 DATE
 ","
-The format is yyyy-MM-dd."
+The date data type."
 "Data Types","TIMESTAMP Type","
 { TIMESTAMP | DATETIME | SMALLDATETIME }
 ","
-The format is yyyy-MM-dd hh:mm:ss[."
+The timestamp data type."
 "Data Types","BINARY Type","
 { BINARY | VARBINARY | LONGVARBINARY | RAW | BYTEA } [ ( precisionInt ) ]
 ","

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

@@ -27,11 +27,10 @@ public class ValueDouble extends Value {
      */
     public static final int DISPLAY_SIZE = 24;
 
-    private static final double DOUBLE_ZERO = 0.0;
-    private static final double DOUBLE_ONE = 1.0;
-    private static final ValueDouble ZERO = new ValueDouble(DOUBLE_ZERO);
-    private static final ValueDouble ONE = new ValueDouble(DOUBLE_ONE);
+    private static final ValueDouble ZERO = new ValueDouble(0.0);
+    private static final ValueDouble ONE = new ValueDouble(1.0);
     private static final ValueDouble NAN = new ValueDouble(Double.NaN);
+    private static final long ZERO_BITS = Double.doubleToLongBits(0.0);
 
     private final double value;
 
@@ -126,10 +125,14 @@ public class ValueDouble extends Value {
      * @return the value
      */
     public static ValueDouble get(double d) {
-        if (DOUBLE_ZERO == d) {
-            return ZERO;
-        } else if (DOUBLE_ONE == d) {
+        if (d == 1.0) {
             return ONE;
+        } else if (d == 0.0) {
+            // unfortunately, -0.0 == 0.0, but we don't want to return
+            // 0.0 in this case
+            if (Double.doubleToLongBits(d) == ZERO_BITS) {
+                return ZERO;
+            }
         } else if (Double.isNaN(d)) {
             return NAN;
         }

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

@@ -27,10 +27,9 @@ public class ValueFloat extends Value {
      */
     static final int DISPLAY_SIZE = 15;
 
-    private static final float FLOAT_ZERO = 0.0F;
-    private static final float FLOAT_ONE = 1.0F;
-    private static final ValueFloat ZERO = new ValueFloat(FLOAT_ZERO);
-    private static final ValueFloat ONE = new ValueFloat(FLOAT_ONE);
+    private static final ValueFloat ZERO = new ValueFloat(0.0F);
+    private static final ValueFloat ONE = new ValueFloat(1.0F);
+    private static final int ZERO_BITS = Float.floatToIntBits(0.0F);
 
     private final float value;
 
@@ -126,10 +125,14 @@ public class ValueFloat extends Value {
      * @return the value
      */
     public static ValueFloat get(float d) {
-        if (FLOAT_ZERO == d) {
-            return ZERO;
-        } else if (FLOAT_ONE == d) {
+        if (d == 1.0F) {
             return ONE;
+        } else if (d == 0.0F) {
+            // unfortunately, -0.0 == 0.0, but we don't want to return
+            // 0.0 in this case
+            if (Float.floatToIntBits(d) == ZERO_BITS) {
+                return ZERO;
+            }
         }
         return (ValueFloat) Value.cache(new ValueFloat(d));
     }

h2/src/test/org/h2/test/test-1.3.txt

 --- special grammar and test cases ---------------------------------------------------------------------------------------------
+select -cast(0 as double) nz;
+> NZ
+> -----
+> -0.0
+> rows: 1
+
 select () empty;
 > EMPTY
 > -----