cloud-fan commented on a change in pull request #24246: [SPARK-24252][SQL] Add TableCatalog API URL: https://github.com/apache/spark/pull/24246#discussion_r277325409
########## File path: sql/catalyst/src/main/java/org/apache/spark/sql/catalog/v2/TableChange.java ########## @@ -0,0 +1,363 @@ +/* + * 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.spark.sql.catalog.v2; + +import org.apache.spark.sql.types.DataType; + +/** + * TableChange subclasses represent requested changes to a table. These are passed to + * {@link TableCatalog#alterTable}. For example, + * <pre> + * import TableChange._ + * val catalog = Catalogs.load(name) + * catalog.asTableCatalog.alterTable(ident, + * addColumn("x", IntegerType), + * renameColumn("a", "b"), + * deleteColumn("c") + * ) + * </pre> + */ +public interface TableChange { + + /** + * Create a TableChange for setting a table property. + * <p> + * If the property already exists, it will be replaced with the new value. + * + * @param property the property name + * @param value the new property value + * @return a TableChange for the addition + */ + static TableChange setProperty(String property, String value) { + return new SetProperty(property, value); + } + + /** + * Create a TableChange for removing a table property. + * <p> + * If the property does not exist, the change will succeed. + * + * @param property the property name + * @return a TableChange for the addition + */ + static TableChange removeProperty(String property) { + return new RemoveProperty(property); + } + + /** + * Create a TableChange for adding an optional column. + * <p> + * If the field already exists, the change will result in an {@link IllegalArgumentException}. + * If the new field is nested and its parent does not exist or is not a struct, the change will + * result in an {@link IllegalArgumentException}. + * + * @param fieldNames field names of the new column + * @param dataType the new column's data type + * @return a TableChange for the addition + */ + static TableChange addColumn(String[] fieldNames, DataType dataType) { + return new AddColumn(fieldNames, dataType, true, null); + } + + /** + * Create a TableChange for adding a column. + * <p> + * If the field already exists, the change will result in an {@link IllegalArgumentException}. + * If the new field is nested and its parent does not exist or is not a struct, the change will + * result in an {@link IllegalArgumentException}. + * + * @param fieldNames field names of the new column + * @param dataType the new column's data type + * @param isNullable whether the new column can contain null + * @return a TableChange for the addition + */ + static TableChange addColumn(String[] fieldNames, DataType dataType, boolean isNullable) { + return new AddColumn(fieldNames, dataType, isNullable, null); + } + + /** + * Create a TableChange for adding a column. + * <p> + * If the field already exists, the change will result in an {@link IllegalArgumentException}. + * If the new field is nested and its parent does not exist or is not a struct, the change will + * result in an {@link IllegalArgumentException}. + * + * @param fieldNames field names of the new column + * @param dataType the new column's data type + * @param isNullable whether the new column can contain null + * @param comment the new field's comment string + * @return a TableChange for the addition + */ + static TableChange addColumn( + String[] fieldNames, + DataType dataType, + boolean isNullable, + String comment) { + return new AddColumn(fieldNames, dataType, isNullable, comment); + } + + /** + * Create a TableChange for renaming a field. + * <p> + * The name is used to find the field to rename. The new name will replace the leaf field name. + * For example, renameColumn("a.b.c", "x") should produce column a.b.x. + * <p> + * If the field does not exist, the change will result in an {@link IllegalArgumentException}. + * + * @param fieldNames the current field names + * @param newName the new name + * @return a TableChange for the rename + */ + static TableChange renameColumn(String[] fieldNames, String newName) { + return new RenameColumn(fieldNames, newName); + } + + /** + * Create a TableChange for updating the type of a field that is nullable. + * <p> + * The field names are used to find the field to update. + * <p> + * If the field does not exist, the change will result in an {@link IllegalArgumentException}. + * + * @param fieldNames field names of the column to update + * @param newDataType the new data type + * @return a TableChange for the update + */ + static TableChange updateColumn(String[] fieldNames, DataType newDataType) { + return new UpdateColumn(fieldNames, newDataType, true); + } + + /** + * Create a TableChange for updating the type of a field. + * <p> + * The field names are used to find the field to update. + * <p> + * If the field does not exist, the change will result in an {@link IllegalArgumentException}. + * + * @param fieldNames field names of the column to update + * @param newDataType the new data type + * @return a TableChange for the update + */ + static TableChange updateColumn(String[] fieldNames, DataType newDataType, boolean isNullable) { + return new UpdateColumn(fieldNames, newDataType, isNullable); + } + + /** + * Create a TableChange for updating the comment of a field. + * <p> + * The name is used to find the field to update. + * <p> + * If the field does not exist, the change will result in an {@link IllegalArgumentException}. + * + * @param fieldNames field names of the column to update + * @param newComment the new comment + * @return a TableChange for the update + */ + static TableChange updateComment(String[] fieldNames, String newComment) { + return new UpdateColumnComment(fieldNames, newComment); + } + + /** + * Create a TableChange for deleting a field. + * <p> + * If the field does not exist, the change will result in an {@link IllegalArgumentException}. + * + * @param fieldNames field names of the column to delete + * @return a TableChange for the delete + */ + static TableChange deleteColumn(String[] fieldNames) { + return new DeleteColumn(fieldNames); + } + + /** + * A TableChange to set a table property. + * <p> + * If the property already exists, it must be replaced with the new value. + */ + final class SetProperty implements TableChange { + private final String property; + private final String value; + + private SetProperty(String property, String value) { + this.property = property; + this.value = value; + } + + public String property() { + return property; + } + + public String value() { + return value; + } + } + + /** + * A TableChange to remove a table property. + * <p> + * If the property does not exist, the change should succeed. + */ + final class RemoveProperty implements TableChange { + private final String property; + + private RemoveProperty(String property) { + this.property = property; + } + + public String property() { + return property; + } + } + + /** + * A TableChange to add a field. + * <p> + * If the field already exists, the change must result in an {@link IllegalArgumentException}. + * If the new field is nested and its parent does not exist or is not a struct, the change must + * result in an {@link IllegalArgumentException}. + */ + final class AddColumn implements TableChange { + private final String[] fieldNames; + private final DataType dataType; + private final boolean isNullable; + private final String comment; + + private AddColumn(String[] fieldNames, DataType dataType, boolean isNullable, String comment) { + this.fieldNames = fieldNames; + this.dataType = dataType; + this.isNullable = isNullable; + this.comment = comment; + } + + public String[] fieldNames() { + return fieldNames; + } + + public DataType dataType() { + return dataType; + } + + public boolean isNullable() { + return isNullable; + } + + public String comment() { + return comment; + } + } + + /** + * A TableChange to rename a field. + * <p> + * The name is used to find the field to rename. The new name will replace the leaf field name. + * For example, renameColumn("a.b.c", "x") should produce column a.b.x. + * <p> + * If the field does not exist, the change must result in an {@link IllegalArgumentException}. + */ + final class RenameColumn implements TableChange { + private final String[] fieldNames; + private final String newName; + + private RenameColumn(String[] fieldNames, String newName) { + this.fieldNames = fieldNames; + this.newName = newName; + } + + public String[] fieldNames() { + return fieldNames; + } + + public String newName() { + return newName; + } + } + + /** + * A TableChange to update the type of a field. + * <p> + * The field names are used to find the field to update. + * <p> + * If the field does not exist, the change must result in an {@link IllegalArgumentException}. + */ + final class UpdateColumn implements TableChange { + private final String[] fieldNames; + private final DataType newDataType; + private final boolean isNullable; + + private UpdateColumn(String[] fieldNames, DataType newDataType, boolean isNullable) { + this.fieldNames = fieldNames; + this.newDataType = newDataType; + this.isNullable = isNullable; + } + + public String[] fieldNames() { + return fieldNames; + } + + public DataType newDataType() { + return newDataType; + } + + public boolean isNullable() { + return isNullable; + } + } + + /** + * A TableChange to update the comment of a field. + * <p> + * The field names are used to find the field to update. + * <p> + * If the field does not exist, the change must result in an {@link IllegalArgumentException}. + */ + final class UpdateColumnComment implements TableChange { Review comment: if users update the column type and comment together via one SQL command, shall we create a `UpdateColumn` table change so that catalog can make it atomic? Or this doesn't matter too much and we just issue 2 catalog actions? ---------------------------------------------------------------- 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. For queries about this service, please contact Infrastructure at: [email protected] With regards, Apache Git Services --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
