Issue 292: Support for modulus operator

Added support for modulus operator in expressions

h2/src/docsrc/help/help.csv

@@ -1748,7 +1748,7 @@ ID=1 OR NAME='Hi'
 "
 
 "Other Grammar","Factor","
-term [ { { * | / } term } [...] ]
+term [ { { * | / | % } term } [...] ]
 ","
 A value or a numeric factor.
 ","

h2/src/docsrc/html/changelog.html

@@ -18,7 +18,9 @@ Change Log
 <h1>Change Log</h1>
 
 <h2>Next Version (unreleased)</h2>
-<ul><li>Issue 288: Some right outer join queries failed to produce the correct result or
+<ul>
+<li>Support for the % operator (modulo) thanks to Noel Grandin.
+</li><li>Issue 288: Some right outer join queries failed to produce the correct result or
     threw exceptions such as "column x must be in the group by list".
 </li><li>Some right outer joins with invalid column referenced (typos) threw a NullPointerException instead of
     "column not found" exception.

h2/src/docsrc/html/roadmap.html

@@ -181,7 +181,6 @@ See also <a href="build.html#providing_patches">Providing Patches</a>.
 </li><li>Compatibility with Derby and PostgreSQL: VALUES(1), (2); SELECT * FROM (VALUES (1), (2)) AS myTable(c1). Issue 221.
 </li><li>Allow execution time prepare for SELECT * FROM CSVREAD(?, 'columnNameString')
 </li><li>Support data type INTERVAL
-</li><li>Support % operator (modulo).
 </li><li>Support nested transactions (possibly using savepoints internally).
 </li><li>Add a benchmark for bigger databases, and one for many users.
 </li><li>Compression in the result set over TCP/IP.

h2/src/main/org/h2/command/Parser.java

@@ -123,8 +123,8 @@ import org.h2.table.IndexColumn;
 import org.h2.table.RangeTable;
 import org.h2.table.Table;
 import org.h2.table.TableFilter;
-import org.h2.table.TableFilter.TableFilterVisitor;
 import org.h2.table.TableView;
+import org.h2.table.TableFilter.TableFilterVisitor;
 import org.h2.util.MathUtils;
 import org.h2.util.New;
 import org.h2.util.StatementBuilder;
@@ -1996,6 +1996,8 @@ public class Parser {
                 r = new Operation(Operation.MULTIPLY, r, readTerm());
             } else if (readIf("/")) {
                 r = new Operation(Operation.DIVIDE, r, readTerm());
+            } else if (readIf("%")) {
+                r = new Operation(Operation.MODULUS, r, readTerm());
             } else {
                 return r;
             }
@@ -3237,6 +3239,7 @@ public class Parser {
             case '}':
             case '*':
             case '/':
+            case '%':
             case ';':
             case ',':
             case ':':

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

@@ -53,6 +53,11 @@ public class Operation extends Expression {
      */
     public static final int NEGATE = 5;
 
+    /**
+     * This operation represents a modulus as in 5 % 2.
+     */
+    public static final int MODULUS = 6;
+
     private int opType;
     private Expression left, right;
     private int dataType;
@@ -92,6 +97,8 @@ public class Operation extends Expression {
             return "*";
         case DIVIDE:
             return "/";
+        case MODULUS:
+            return "%";
         default:
             throw DbException.throwInternalError("opType=" + opType);
         }
@@ -149,6 +156,11 @@ public class Operation extends Expression {
                 return ValueNull.INSTANCE;
             }
             return l.divide(r);
+        case MODULUS:
+            if (l == ValueNull.INSTANCE || r == ValueNull.INSTANCE) {
+                return ValueNull.INSTANCE;
+            }
+            return l.modulus(r);
         default:
             throw DbException.throwInternalError("type=" + opType);
         }
@@ -181,6 +193,7 @@ public class Operation extends Expression {
         case MINUS:
         case MULTIPLY:
         case DIVIDE:
+        case MODULUS:
             right = right.optimize(session);
             int l = left.getType();
             int r = right.getType();

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

@@ -582,7 +582,7 @@ andCondition [ { OR andCondition } [...] ]
 ","
 Value or condition."
 "Other Grammar","Factor","
-term [ { { * | / } term } [...] ]
+term [ { { * | / | % } term } [...] ]
 ","
 A value or a numeric factor."
 "Other Grammar","Hex","

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

@@ -485,6 +485,16 @@ public abstract class Value {
         throw throwUnsupportedExceptionForType("*");
     }
 
+    /**
+     * Take the modulus with a value and return the result.
+     *
+     * @param v the value to take the modulus with
+     * @return the result
+     */
+    public Value modulus(Value v) {
+        throw throwUnsupportedExceptionForType("%");
+    }
+
     /**
      * Compare a value to the specified type.
      *

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

@@ -72,6 +72,14 @@ public class ValueByte extends Value {
         return ValueByte.get((byte) (value / other.value));
     }
 
+    public Value modulus(Value v) {
+        ValueByte other = (ValueByte) v;
+        if (other.value == 0) {
+            throw DbException.get(ErrorCode.DIVISION_BY_ZERO_1, getSQL());
+        }
+        return ValueByte.get((byte) (value % other.value));
+    }
+
     public String getSQL() {
         return getString();
     }

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

@@ -104,6 +104,15 @@ public class ValueDecimal extends Value {
         return ValueDecimal.get(bd);
     }
 
+    public ValueDecimal modulus(Value v) {
+        ValueDecimal dec = (ValueDecimal) v;
+        if (dec.value.signum() == 0) {
+            throw DbException.get(ErrorCode.DIVISION_BY_ZERO_1, getSQL());
+        }
+        BigDecimal bd = value.remainder(dec.value);
+        return ValueDecimal.get(bd);
+    }
+
     public String getSQL() {
         return getString();
     }

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

@@ -69,6 +69,14 @@ public class ValueDouble extends Value {
         return ValueDouble.get(value / v2.value);
     }
 
+    public ValueDouble modulus(Value v) {
+        ValueDouble other = (ValueDouble) v;
+        if (other.value == 0) {
+            throw DbException.get(ErrorCode.DIVISION_BY_ZERO_1, getSQL());
+        }
+        return ValueDouble.get(value % other.value);
+    }
+
     public String getSQL() {
         if (value == Double.POSITIVE_INFINITY) {
             return "POWER(0, -1)";

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

@@ -68,6 +68,14 @@ public class ValueFloat extends Value {
         return ValueFloat.get(value / v2.value);
     }
 
+    public Value modulus(Value v) {
+        ValueFloat other = (ValueFloat) v;
+        if (other.value == 0) {
+            throw DbException.get(ErrorCode.DIVISION_BY_ZERO_1, getSQL());
+        }
+        return ValueFloat.get(value % other.value);
+    }
+
     public String getSQL() {
         if (value == Float.POSITIVE_INFINITY) {
             return "POWER(0, -1)";

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

@@ -102,6 +102,14 @@ public class ValueInt extends Value {
         return ValueInt.get(value / other.value);
     }
 
+    public Value modulus(Value v) {
+        ValueInt other = (ValueInt) v;
+        if (other.value == 0) {
+            throw DbException.get(ErrorCode.DIVISION_BY_ZERO_1, getSQL());
+        }
+        return ValueInt.get(value % other.value);
+    }
+
     public String getSQL() {
         return getString();
     }

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

@@ -137,6 +137,14 @@ public class ValueLong extends Value {
         return ValueLong.get(value / other.value);
     }
 
+    public Value modulus(Value v) {
+        ValueLong other = (ValueLong) v;
+        if (other.value == 0) {
+            throw DbException.get(ErrorCode.DIVISION_BY_ZERO_1, getSQL());
+        }
+        return ValueLong.get(this.value % other.value);
+    }
+
     public String getSQL() {
         return getString();
     }

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

@@ -72,6 +72,14 @@ public class ValueShort extends Value {
         return ValueShort.get((short) (value / other.value));
     }
 
+    public Value modulus(Value v) {
+        ValueShort other = (ValueShort) v;
+        if (other.value == 0) {
+            throw DbException.get(ErrorCode.DIVISION_BY_ZERO_1, getSQL());
+        }
+        return ValueShort.get((short) (value % other.value));
+    }
+
     public String getSQL() {
         return getString();
     }

h2/src/test/org/h2/test/unit/TestValue.java

@@ -7,6 +7,7 @@
 package org.h2.test.unit;
 
 import java.math.BigDecimal;
+import java.sql.Connection;
 import java.sql.Date;
 import java.sql.ResultSet;
 import java.sql.SQLException;
@@ -14,10 +15,13 @@ import java.sql.Time;
 import java.sql.Timestamp;
 import java.sql.Types;
 import java.util.UUID;
+import org.h2.constant.ErrorCode;
+import org.h2.message.DbException;
 import org.h2.test.TestBase;
 import org.h2.tools.SimpleResultSet;
 import org.h2.value.DataType;
 import org.h2.value.Value;
+import org.h2.value.ValueDecimal;
 import org.h2.value.ValueDouble;
 import org.h2.value.ValueFloat;
 import org.h2.value.ValueResultSet;
@@ -43,6 +47,9 @@ public class TestValue extends TestBase {
         testUUID();
         testDouble(false);
         testDouble(true);
+        testModulusDouble();
+        testModulusDecimal();
+        testModulusOperator();
     }
 
     private void testValueResultSet() throws SQLException {
@@ -159,4 +166,42 @@ public class TestValue extends TestBase {
         assertEquals("00000000-0000-4000-8000-000000000000", min.getString());
     }
 
+    private void testModulusDouble() {
+        ValueDouble vd1 = ValueDouble.get(12);
+        ValueDouble vd2 = ValueDouble.get(10);
+        ValueDouble vd3 = vd1.modulus(vd2);
+        assertEquals(2, vd3.getDouble());
+        try {
+            vd1.modulus(ValueDouble.get(0));
+            fail();
+        } catch (DbException e) {
+            assertEquals(ErrorCode.DIVISION_BY_ZERO_1, e.getErrorCode());
+        }
+    }
+
+    private void testModulusDecimal() {
+        ValueDecimal vd1 = ValueDecimal.get(new BigDecimal(12));
+        ValueDecimal vd2 = ValueDecimal.get(new BigDecimal(10));
+        ValueDecimal vd3 = vd1.modulus(vd2);
+        assertEquals(2, vd3.getDouble());
+        try {
+            vd1.modulus(ValueDecimal.get(new BigDecimal(0)));
+            fail();
+        } catch (DbException e) {
+            assertEquals(ErrorCode.DIVISION_BY_ZERO_1, e.getErrorCode());
+        }
+    }
+
+    private void testModulusOperator() throws SQLException {
+        Connection conn = getConnection("modulus");
+        try {
+            ResultSet rs = conn.createStatement().executeQuery("CALL 12 % 10");
+            rs.next();
+            assertEquals(2, rs.getInt(1));
+        } finally {
+            conn.close();
+            deleteDb("modulus");
+        }
+    }
+
 }

h2/src/tools/org/h2/build/doc/dictionary.txt

@@ -678,5 +678,5 @@ clip upgrades demonstrate inspectors
 exceed identities differentiate inherited tracks strip suggestions
 registration sanity improperly annotate inheritance composite inspected
 hurt imposes marshal policy upgrader configurations dark varray xlint executor
-completion inactivity exports maintains backside schwietzke rene rectangular
+completion inactivity exports maintains backside schwietzke rene rectangular grandin noel
 sine cosine tangent cotangent trigonometric