com.orientechnologies.orient.core.sql.functions.misc.OSQLFunctionIfNull Maven / Gradle / Ivy
/*
*
* * Copyright 2010-2016 OrientDB LTD (http://orientdb.com)
* *
* * Licensed under the Apache License, Version 2.0 (the "License");
* * you may not use this file except in compliance with the License.
* * You may obtain a copy of the License at
* *
* * http://www.apache.org/licenses/LICENSE-2.0
* *
* * Unless required by applicable law or agreed to in writing, software
* * distributed under the License is distributed on an "AS IS" BASIS,
* * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* * See the License for the specific language governing permissions and
* * limitations under the License.
* *
* * For more information: http://orientdb.com
*
*/
package com.orientechnologies.orient.core.sql.functions.misc;
import com.orientechnologies.orient.core.command.OCommandContext;
import com.orientechnologies.orient.core.db.record.OIdentifiable;
import com.orientechnologies.orient.core.sql.functions.OSQLFunctionAbstract;
/**
* Returns the passed field/value (or optional parameter return_value_if_not_null
* ) if field/value is not null; otherwise it returns
* return_value_if_null.
*
* Syntax:
*
*
*
*
* ifnull(<field|value>, <return_value_if_null> [,<return_value_if_not_null>])
*
*
*
*
* Examples:
*
*
*
*
* SELECT ifnull('a', 'b') FROM ...
* -> 'a'
*
* SELECT ifnull('a', 'b', 'c') FROM ...
* -> 'c'
*
* SELECT ifnull(null, 'b') FROM ...
* -> 'b'
*
* SELECT ifnull(null, 'b', 'c') FROM ...
* -> 'b'
*
*
*
*
* @author Mark Bigler
*/
public class OSQLFunctionIfNull extends OSQLFunctionAbstract {
public static final String NAME = "ifnull";
public OSQLFunctionIfNull() {
super(NAME, 2, 3);
}
@Override
public Object execute(
Object iThis,
final OIdentifiable iCurrentRecord,
final Object iCurrentResult,
final Object[] iParams,
final OCommandContext iContext) {
/*
* iFuncParams [0] field/value to check for null [1] return value if [0] is null [2] optional return value if [0] is not null
*/
if (iParams[0] != null) {
if (iParams.length == 3) {
return iParams[2];
}
return iParams[0];
}
return iParams[1];
}
@Override
public String getSyntax() {
return "Syntax error: ifnull(, [,])";
}
}