xuzifu666 commented on code in PR #4249: URL: https://github.com/apache/calcite/pull/4249#discussion_r2006904331
########## core/src/main/java/org/apache/calcite/sql/dialect/TrinoSqlDialect.java: ########## @@ -0,0 +1,78 @@ +/* + * 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 org.apache.calcite.sql.dialect; + +import org.apache.calcite.avatica.util.Casing; +import org.apache.calcite.config.NullCollation; +import org.apache.calcite.sql.SqlCall; +import org.apache.calcite.sql.SqlDialect; +import org.apache.calcite.sql.SqlNode; +import org.apache.calcite.sql.SqlWriter; +import org.apache.calcite.sql.fun.SqlLibraryOperators; +import org.apache.calcite.sql.fun.SqlStdOperatorTable; +import org.apache.calcite.sql.parser.SqlParserPos; +import org.apache.calcite.util.RelToSqlConverterUtil; + +import org.checkerframework.checker.nullness.qual.Nullable; + +/** + * A <code>SqlDialect</code> implementation for the Trino database. + */ +public class TrinoSqlDialect extends PrestoSqlDialect { + public static final Context DEFAULT_CONTEXT = SqlDialect.EMPTY_CONTEXT + .withDatabaseProduct(DatabaseProduct.TRINO) + .withIdentifierQuoteString("\"") + .withUnquotedCasing(Casing.UNCHANGED) + .withNullCollation(NullCollation.LAST); + + public static final SqlDialect DEFAULT = new TrinoSqlDialect(DEFAULT_CONTEXT); + + /** + * Creates a TrinoSqlDialect. + */ + public TrinoSqlDialect(Context context) { + super(context); + } + + @Override public void unparseOffsetFetch(SqlWriter writer, @Nullable SqlNode offset, + @Nullable SqlNode fetch) { + unparseFetchUsingAnsi(writer, offset, fetch); + } + + @Override public void unparseCall(SqlWriter writer, SqlCall call, + int leftPrec, int rightPrec) { + if (call.getOperator() == SqlStdOperatorTable.APPROX_COUNT_DISTINCT) { + RelToSqlConverterUtil.specialOperatorByName("APPROX_DISTINCT") + .unparse(writer, call, 0, 0); + } else { + switch (call.getKind()) { + case MAP_VALUE_CONSTRUCTOR: + super.unparseMapValue(writer, call, leftPrec, rightPrec); + break; + case CHAR_LENGTH: + SqlCall lengthCall = SqlLibraryOperators.LENGTH + .createCall(SqlParserPos.ZERO, call.getOperandList()); + super.unparseCall(writer, lengthCall, leftPrec, rightPrec); + break; + default: + // Current impl is same with Postgresql. + PostgresqlSqlDialect.DEFAULT.unparseCall(writer, call, leftPrec, rightPrec); Review Comment: According my test about trino，here still not found other differences，and if had found I and others would fix it directly，much of syntax keep the same behavior with presto，so IMO here can keep it firstly @NobiGo -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
