com.hazelcast.org.apache.calcite.sql.fun.SqlCursorConstructor Maven / Gradle / Ivy
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* 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 com.hazelcast.com.liance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.com.hazelcast.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.rel.type.RelDataType;
import com.hazelcast.org.apache.calcite.sql.SqlCall;
import com.hazelcast.org.apache.calcite.sql.SqlKind;
import com.hazelcast.org.apache.calcite.sql.SqlSelect;
import com.hazelcast.org.apache.calcite.sql.SqlSpecialOperator;
import com.hazelcast.org.apache.calcite.sql.SqlWriter;
import com.hazelcast.org.apache.calcite.sql.type.OperandTypes;
import com.hazelcast.org.apache.calcite.sql.type.ReturnTypes;
import com.hazelcast.org.apache.calcite.sql.validate.SqlValidator;
import com.hazelcast.org.apache.calcite.sql.validate.SqlValidatorScope;
/**
* SqlCursorConstructor defines the non-standard CURSOR(<query>)
* constructor.
*/
public class SqlCursorConstructor extends SqlSpecialOperator {
//~ Constructors -----------------------------------------------------------
public SqlCursorConstructor() {
super(
"CURSOR",
SqlKind.CURSOR, MDX_PRECEDENCE,
false,
ReturnTypes.CURSOR,
null,
OperandTypes.ANY);
}
//~ Methods ----------------------------------------------------------------
public RelDataType deriveType(
SqlValidator validator,
SqlValidatorScope scope,
SqlCall call) {
SqlSelect subSelect = call.operand(0);
validator.declareCursor(subSelect, scope);
subSelect.validateExpr(validator, scope);
return super.deriveType(validator, scope, call);
}
public void unparse(
SqlWriter writer,
SqlCall call,
int leftPrec,
int rightPrec) {
writer.keyword("CURSOR");
final SqlWriter.Frame frame = writer.startList("(", ")");
assert call.operandCount() == 1;
call.operand(0).unparse(writer, leftPrec, rightPrec);
writer.endList(frame);
}
public boolean argumentMustBeScalar(int ordinal) {
return false;
}
}