vvysotskyi commented on a change in pull request #1615: DRILL-6964: Implement CREATE / DROP TABLE SCHEMA commands URL: https://github.com/apache/drill/pull/1615#discussion_r249442649
########## File path: exec/java-exec/src/main/java/org/apache/drill/exec/record/metadata/schema/parser/TableSchemaVisitor.java ########## @@ -0,0 +1,247 @@ +/* + * 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.drill.exec.record.metadata.schema.parser; + +import org.antlr.v4.runtime.tree.TerminalNode; +import org.apache.drill.common.types.TypeProtos; +import org.apache.drill.common.types.Types; +import org.apache.drill.exec.record.MaterializedField; +import org.apache.drill.exec.record.metadata.ColumnMetadata; +import org.apache.drill.exec.record.metadata.MapBuilder; +import org.apache.drill.exec.record.metadata.MetadataUtils; +import org.apache.drill.exec.record.metadata.RepeatedListBuilder; +import org.apache.drill.exec.record.metadata.TupleMetadata; +import org.apache.drill.exec.record.metadata.TupleSchema; + +import java.util.List; + +/** + * Visits table schema and stores metadata about its columns into {@link TupleMetadata} class. + */ +public class TableSchemaVisitor extends TableSchemaParserBaseVisitor<TupleMetadata> { + + @Override + public TupleMetadata visitSchema(TableSchemaParser.SchemaContext ctx) { + return visitColumns(ctx.columns()); + } + + @Override + public TupleMetadata visitColumns(TableSchemaParser.ColumnsContext ctx) { + TupleMetadata schema = new TupleSchema(); + ColumnVisitor columnVisitor = new ColumnVisitor(); + ctx.column().forEach( + c -> schema.addColumn(c.accept(columnVisitor)) + ); + return schema; + } + + /** + * Visits various types of columns (primitive, map, array) and stores their metadata + * into {@link ColumnMetadata} class. + */ + public static class ColumnVisitor extends TableSchemaParserBaseVisitor<ColumnMetadata> { + + @Override + public ColumnMetadata visitPrimitive_column(TableSchemaParser.Primitive_columnContext ctx) { + String name = ctx.column_id().accept(new IdVisitor()); + TypeProtos.DataMode mode = ctx.nullability() == null ? TypeProtos.DataMode.OPTIONAL : TypeProtos.DataMode.REQUIRED; + return ctx.simple_type().accept(new TypeVisitor(name, mode)); + } + + @Override + public ColumnMetadata visitSimple_array_column(TableSchemaParser.Simple_array_columnContext ctx) { + String name = ctx.column_id().accept(new IdVisitor()); + return ctx.simple_array_type().accept(new ArrayTypeVisitor(name)); + } + + @Override + public ColumnMetadata visitMap_column(TableSchemaParser.Map_columnContext ctx) { + String name = ctx.column_id().accept(new IdVisitor()); + // Drill does not distinguish between nullable and not null map, by default they are not null + return ctx.map_type().accept(new TypeVisitor(name, TypeProtos.DataMode.REQUIRED)); + } + + @Override + public ColumnMetadata visitComplex_array_column(TableSchemaParser.Complex_array_columnContext ctx) { + String name = ctx.column_id().accept(new IdVisitor()); + ColumnMetadata child = ctx.complex_array_type().complex_type().accept(new ArrayTypeVisitor(name)); + RepeatedListBuilder builder = new RepeatedListBuilder(null, name); + builder.addColumn(child); + return builder.buildColumn(); + } + + } + + /** + * Visits ID and QUOTED_ID, returning their string representation. + */ + private static class IdVisitor extends TableSchemaParserBaseVisitor<String> { + + @Override + public String visitId(TableSchemaParser.IdContext ctx) { + return ctx.ID().getText(); + } + + @Override + public String visitQuoted_id(TableSchemaParser.Quoted_idContext ctx) { + String text = ctx.QUOTED_ID().getText(); + // first substring first and last symbols (backticks) + // then find all chars that are preceding with the backslash and remove the backslash + return text.substring(1, text.length() -1).replaceAll("\\\\(.)", "$1"); + } + } + + /** + * Visits simple and map types, storing their metadata into {@link ColumnMetadata} holder. + */ + private static class TypeVisitor extends TableSchemaParserBaseVisitor<ColumnMetadata> { + + private final String name; + private final TypeProtos.DataMode mode; + + TypeVisitor(String name, TypeProtos.DataMode mode) { + this.name = name; + this.mode = mode; + } + + @Override + public ColumnMetadata visitInt(TableSchemaParser.IntContext ctx) { + return constructColumn(Types.withMode(TypeProtos.MinorType.INT, mode)); + } + + @Override + public ColumnMetadata visitBigint(TableSchemaParser.BigintContext ctx) { + return constructColumn(Types.withMode(TypeProtos.MinorType.BIGINT, mode)); + } + + @Override + public ColumnMetadata visitFloat(TableSchemaParser.FloatContext ctx) { + return constructColumn(Types.withMode(TypeProtos.MinorType.FLOAT4, mode)); + } + + @Override + public ColumnMetadata visitDouble(TableSchemaParser.DoubleContext ctx) { + return constructColumn(Types.withMode(TypeProtos.MinorType.FLOAT8, mode)); + } + + @Override + public ColumnMetadata visitDecimal(TableSchemaParser.DecimalContext ctx) { + TypeProtos.MajorType type = Types.withMode(TypeProtos.MinorType.VARDECIMAL, mode); + + List<TerminalNode> numbers = ctx.NUMBER(); + if (!numbers.isEmpty()) { + int precision = Integer.parseInt(numbers.get(0).getText()); + int scale = numbers.size() == 2 ? Integer.parseInt(numbers.get(1).getText()) : 0; + type = type.toBuilder().setPrecision(precision).setScale(scale).build(); + } + + return constructColumn(type); + } + + @Override + public ColumnMetadata visitBoolean(TableSchemaParser.BooleanContext ctx) { + return constructColumn(Types.withMode(TypeProtos.MinorType.BIT, mode)); + } + + @Override + public ColumnMetadata visitVarchar(TableSchemaParser.VarcharContext ctx) { + TypeProtos.MajorType type = Types.withMode(TypeProtos.MinorType.VARCHAR, mode); + + if (ctx.NUMBER() != null) { + type = type.toBuilder().setPrecision(Integer.parseInt(ctx.NUMBER().getText())).build(); + } + + return constructColumn(type); + } + + @Override + public ColumnMetadata visitBinary(TableSchemaParser.BinaryContext ctx) { + TypeProtos.MajorType type = Types.withMode(TypeProtos.MinorType.VARBINARY, mode); + + if (ctx.NUMBER() != null) { + type = type.toBuilder().setPrecision(Integer.parseInt(ctx.NUMBER().getText())).build(); + } + + return constructColumn(type); + } + + @Override + public ColumnMetadata visitTime(TableSchemaParser.TimeContext ctx) { + return constructColumn(Types.withMode(TypeProtos.MinorType.TIME, mode)); Review comment: Precision for TIME and TIMESTAMP ---------------------------------------------------------------- This is an automated message from the Apache Git Service. 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