Issue #229: DATEDIFF does not work for 'WEEK'

h2/src/docsrc/html/changelog.html

@@ -21,6 +21,8 @@ Change Log
 
 <h2>Next Version (unreleased)</h2>
 <ul>
+<li>Issue #229: DATEDIFF does not work for 'WEEK'
+</li>
 <li>Issue #156: Add support for getGeneratedKeys() when executing commands via PreparedStatement#executeBatch
 </li>
 <li>Issue #195: The new Maven uses a .cmd file instead of a .bat file

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

@@ -21,7 +21,6 @@ import java.util.HashMap;
 import java.util.Locale;
 import java.util.TimeZone;
 import java.util.regex.PatternSyntaxException;
-
 import org.h2.api.ErrorCode;
 import org.h2.command.Command;
 import org.h2.command.Parser;
@@ -1819,7 +1818,9 @@ public class Function extends Expression implements FunctionCall {
             return t2 - t1;
         case Calendar.SECOND:
         case Calendar.MINUTE:
-        case Calendar.HOUR_OF_DAY: {
+        case Calendar.HOUR_OF_DAY:
+        case Calendar.DAY_OF_YEAR:
+        case Calendar.WEEK_OF_YEAR: {
             // first 'normalize' the numbers so both are not negative
             long hour = 60 * 60 * 1000;
             long add = Math.min(t1 / hour * hour, t2 / hour * hour);
@@ -1832,6 +1833,10 @@ public class Function extends Expression implements FunctionCall {
                 return t2 / (60 * 1000) - t1 / (60 * 1000);
             case Calendar.HOUR_OF_DAY:
                 return t2 / hour - t1 / hour;
+            case Calendar.DAY_OF_YEAR:
+                return t2 / (hour * 24) - t1 / (hour * 24);
+            case Calendar.WEEK_OF_YEAR:
+                return t2 / (hour * 24 * 7) - t1 / (hour * 24 * 7);
             default:
                 throw DbException.throwInternalError("field:" + field);
             }
@@ -1849,9 +1854,12 @@ public class Function extends Expression implements FunctionCall {
         int month2 = calendar.get(Calendar.MONTH);
         int result = year2 - year1;
         if (field == Calendar.MONTH) {
-            result = 12 * result + (month2 - month1);
-        }
+            return 12 * result + (month2 - month1);
+        } else if (field == Calendar.YEAR) {
             return result;
+        } else {
+            throw DbException.getUnsupportedException("DATEDIFF " + part);
+        }
     }
 
     private static String substring(String s, int start, int length) {

h2/src/test/org/h2/test/testScript.sql

@@ -3964,6 +3964,12 @@ SELECT DATEDIFF('HOUR', '1900-01-01 01:00:00.001', '1900-01-01 01:00:01.000'), D
 > 0 0
 > rows: 1
 
+select datediff(day, '2015-12-09 23:59:00.0', '2016-01-16 23:59:00.0'), datediff(wk, '2015-12-09 23:59:00.0', '2016-01-16 23:59:00.0');
+> 38 5
+> -- -
+> 38 5
+> rows: 1
+
 create table test(id int);
 > ok