ROUND(..) now also works with just one parameter.

h2/src/docsrc/help/help.csv

@@ -2660,9 +2660,9 @@ RANDOM_UUID()
 "
 
 "Functions (Numeric)","ROUND","
-ROUND(numeric, digitsInt)
+ROUND(numeric [, digitsInt])
 ","
-Rounds to a number of digits.
+Rounds to a number of digits, or to the nearest long if the number of digits if not set.
 This method returns a double.
 ","
 ROUND(VALUE, 2)

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

@@ -189,7 +189,7 @@ public class Function extends Expression implements FunctionCall {
         // RAND with one argument: seed the random generator
         addFunctionNotDeterministic("RAND", RAND, VAR_ARGS, Value.DOUBLE);
         addFunctionNotDeterministic("RANDOM", RAND, VAR_ARGS, Value.DOUBLE);
-        addFunction("ROUND", ROUND, 2, Value.DOUBLE);
+        addFunction("ROUND", ROUND, VAR_ARGS, Value.DOUBLE);
         addFunction("ROUNDMAGIC", ROUNDMAGIC, 1, Value.DOUBLE);
         addFunction("SIGN", SIGN, 1, Value.INT);
         addFunction("SIN", SIN, 1, Value.DOUBLE);
@@ -925,7 +925,7 @@ public class Function extends Expression implements FunctionCall {
             result = ValueDouble.get(Math.pow(v0.getDouble(), v1.getDouble()));
             break;
         case ROUND: {
-            double f = Math.pow(10., v1.getDouble());
+            double f = v1 == null ? 1. : Math.pow(10., v1.getDouble());
             result = ValueDouble.get(Math.round(v0.getDouble() * f) / f);
             break;
         }
@@ -1595,6 +1595,7 @@ public class Function extends Expression implements FunctionCall {
         case RTRIM:
         case TRIM:
         case FILE_READ:
+        case ROUND:
             min = 1;
             max = 2;
             break;

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

@@ -9024,6 +9024,12 @@ select round(null, null) en, round(10.49, 0) e10, round(10.05, 1) e101 from test
 > null 10.0 10.1
 > rows: 1
 
+select round(null) en, round(0.6, null) en2, round(1.05) e1, round(-1.51) em2 from test;
+> EN   EN2  E1  EM2
+> ---- ---- --- ----
+> null null 1.0 -2.0
+> rows: 1
+
 select roundmagic(null) en, roundmagic(cast(3.11 as double) - 3.1) e001, roundmagic(3.11-3.1-0.01) e000, roundmagic(2000000000000) e20x from test;
 > EN   E001 E000 E20X
 > ---- ---- ---- ------