com.hazelcast.org.apache.calcite.sql.fun.SqlTimestampDiffFunction Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to you 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.
*/
package com.hazelcast.org.apache.calcite.sql.fun;
import com.hazelcast.org.apache.calcite.avatica.util.TimeUnit;
import com.hazelcast.org.apache.calcite.rel.type.RelDataTypeFactory;
import com.hazelcast.org.apache.calcite.sql.SqlFunction;
import com.hazelcast.org.apache.calcite.sql.SqlFunctionCategory;
import com.hazelcast.org.apache.calcite.sql.SqlKind;
import com.hazelcast.org.apache.calcite.sql.type.OperandTypes;
import com.hazelcast.org.apache.calcite.sql.type.SqlReturnTypeInference;
import com.hazelcast.org.apache.calcite.sql.type.SqlTypeFamily;
import com.hazelcast.org.apache.calcite.sql.type.SqlTypeName;
/**
* The TIMESTAMPDIFF
function, which calculates the difference
* between two timestamps.
*
* The SQL syntax is
*
*
* TIMESTAMPDIFF(timestamp interval, timestamp,
* timestamp)
*
*
* The interval time unit can one of the following literals:
* - NANOSECOND (and synonym SQL_TSI_FRAC_SECOND)
*
- MICROSECOND (and synonyms SQL_TSI_MICROSECOND, FRAC_SECOND)
*
- SECOND (and synonym SQL_TSI_SECOND)
*
- MINUTE (and synonym SQL_TSI_MINUTE)
*
- HOUR (and synonym SQL_TSI_HOUR)
*
- DAY (and synonym SQL_TSI_DAY)
*
- WEEK (and synonym SQL_TSI_WEEK)
*
- MONTH (and synonym SQL_TSI_MONTH)
*
- QUARTER (and synonym SQL_TSI_QUARTER)
*
- YEAR (and synonym SQL_TSI_YEAR)
*
*
* Returns difference between two timestamps in indicated timestamp
* interval.
*/
class SqlTimestampDiffFunction extends SqlFunction {
/** Creates a SqlTimestampDiffFunction. */
private static final SqlReturnTypeInference RETURN_TYPE_INFERENCE =
opBinding -> {
final RelDataTypeFactory typeFactory = opBinding.getTypeFactory();
SqlTypeName sqlTypeName =
opBinding.getOperandLiteralValue(0, TimeUnit.class) == TimeUnit.NANOSECOND
? SqlTypeName.BIGINT
: SqlTypeName.INTEGER;
return typeFactory.createTypeWithNullability(
typeFactory.createSqlType(sqlTypeName),
opBinding.getOperandType(1).isNullable()
|| opBinding.getOperandType(2).isNullable());
};
SqlTimestampDiffFunction() {
super("TIMESTAMPDIFF", SqlKind.TIMESTAMP_DIFF,
RETURN_TYPE_INFERENCE, null,
OperandTypes.family(SqlTypeFamily.ANY, SqlTypeFamily.DATETIME,
SqlTypeFamily.DATETIME),
SqlFunctionCategory.TIMEDATE);
}
}