com.hazelcast.jet.sql.impl.aggregate.function.HazelcastCountAggFunction Maven / Gradle / Ivy
/*
* Copyright 2021 Hazelcast Inc.
*
* Licensed under the Hazelcast Community License (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://hazelcast.com/hazelcast-community-license
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.hazelcast.jet.sql.impl.aggregate.function;
import com.hazelcast.jet.sql.impl.validate.HazelcastCallBinding;
import com.hazelcast.jet.sql.impl.validate.operators.typeinference.ReplaceUnknownOperandTypeInference;
import com.hazelcast.jet.sql.impl.validate.operators.common.HazelcastAggFunction;
import com.hazelcast.jet.sql.impl.validate.param.NoOpParameterConverter;
import com.hazelcast.jet.sql.impl.validate.types.HazelcastIntegerType;
import com.hazelcast.org.apache.calcite.rel.type.RelDataType;
import com.hazelcast.org.apache.calcite.sql.SqlCall;
import com.hazelcast.org.apache.calcite.sql.SqlCallBinding;
import com.hazelcast.org.apache.calcite.sql.SqlDynamicParam;
import com.hazelcast.org.apache.calcite.sql.SqlFunctionCategory;
import com.hazelcast.org.apache.calcite.sql.SqlKind;
import com.hazelcast.org.apache.calcite.sql.SqlNode;
import com.hazelcast.org.apache.calcite.sql.SqlSyntax;
import com.hazelcast.org.apache.calcite.sql.type.SqlOperandTypeInference;
import com.hazelcast.org.apache.calcite.sql.validate.SqlValidator;
import com.hazelcast.org.apache.calcite.sql.validate.SqlValidatorScope;
import com.hazelcast.org.apache.calcite.util.Optionality;
import static com.hazelcast.org.apache.calcite.sql.type.SqlTypeName.BIGINT;
public class HazelcastCountAggFunction extends HazelcastAggFunction {
public HazelcastCountAggFunction() {
super(
"COUNT",
SqlKind.COUNT,
opBinding -> HazelcastIntegerType.create(Long.SIZE, false),
new IgnoreCountStarOperandTypeInference(new ReplaceUnknownOperandTypeInference(BIGINT)),
null,
SqlFunctionCategory.NUMERIC,
false,
false,
Optionality.FORBIDDEN);
}
@Override
public SqlSyntax getSyntax() {
return SqlSyntax.FUNCTION_STAR;
}
@Override
public RelDataType deriveType(
SqlValidator validator,
SqlValidatorScope scope,
SqlCall call
) {
return HazelcastIntegerType.create(Long.SIZE, false);
}
protected boolean checkOperandTypes(HazelcastCallBinding binding, boolean throwOnFailure) {
SqlNode node = binding.operand(0);
if (node.getKind() == SqlKind.DYNAMIC_PARAM) {
int parameterIndex = ((SqlDynamicParam) node).getIndex();
binding.getValidator().setParameterConverter(parameterIndex, NoOpParameterConverter.INSTANCE);
}
// COUNT accepts any operand type
return true;
}
/**
* A wrapper for {@link SqlOperandTypeInference} that does nothing if the
* call is COUNT(*). In other case it delegates to the wrapped inference.
*/
private static class IgnoreCountStarOperandTypeInference implements SqlOperandTypeInference {
private final SqlOperandTypeInference delegate;
IgnoreCountStarOperandTypeInference(SqlOperandTypeInference delegate) {
this.delegate = delegate;
}
@Override
public void inferOperandTypes(SqlCallBinding callBinding, RelDataType returnType, RelDataType[] operandTypes) {
if (callBinding.getCall().isCountStar()) {
return;
}
delegate.inferOperandTypes(callBinding, returnType, operandTypes);
}
}
}