| /* |
| * 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.planner.sql.handlers; |
| |
| import java.io.IOException; |
| |
| import org.apache.calcite.rel.type.RelDataType; |
| import org.apache.calcite.schema.Schema; |
| import org.apache.calcite.schema.SchemaPlus; |
| import org.apache.calcite.schema.Table; |
| import org.apache.calcite.tools.RelConversionException; |
| import org.apache.calcite.tools.ValidationException; |
| |
| import org.apache.drill.common.exceptions.UserException; |
| import org.apache.drill.common.util.DrillStringUtils; |
| import org.apache.drill.exec.dotdrill.View; |
| import org.apache.drill.exec.ops.QueryContext; |
| import org.apache.drill.exec.physical.PhysicalPlan; |
| import org.apache.drill.exec.planner.sql.DirectPlan; |
| import org.apache.drill.exec.planner.sql.SchemaUtilities; |
| import org.apache.drill.exec.planner.sql.parser.SqlCreateView; |
| import org.apache.drill.exec.planner.sql.parser.SqlDropView; |
| import org.apache.drill.exec.store.AbstractSchema; |
| import org.apache.drill.exec.work.foreman.ForemanSetupException; |
| import org.apache.calcite.rel.RelNode; |
| import org.apache.calcite.sql.SqlNode; |
| |
| public abstract class ViewHandler extends DefaultSqlHandler { |
| private static final org.slf4j.Logger logger = org.slf4j.LoggerFactory.getLogger(ViewHandler.class); |
| |
| protected QueryContext context; |
| |
| public ViewHandler(SqlHandlerConfig config) { |
| super(config); |
| this.context = config.getContext(); |
| } |
| |
| /** Handler for Create View DDL command */ |
| public static class CreateView extends ViewHandler { |
| |
| public CreateView(SqlHandlerConfig config) { |
| super(config); |
| } |
| |
| @Override |
| public PhysicalPlan getPlan(SqlNode sqlNode) throws ValidationException, RelConversionException, IOException, ForemanSetupException { |
| SqlCreateView createView = unwrap(sqlNode, SqlCreateView.class); |
| |
| final String newViewName = DrillStringUtils.removeLeadingSlash(createView.getName()); |
| |
| // Disallow temporary tables usage in view definition |
| config.getConverter().disallowTemporaryTables(); |
| // Store the viewSql as view def SqlNode is modified as part of the resolving the new table definition below. |
| // Use of parentheses is forced to ensure expressions are read correctly. |
| final String viewSql = createView.getQuery().toSqlString(null, true).getSql(); |
| final ConvertedRelNode convertedRelNode = validateAndConvert(createView.getQuery()); |
| final RelDataType validatedRowType = convertedRelNode.getValidatedRowType(); |
| final RelNode queryRelNode = convertedRelNode.getConvertedNode(); |
| |
| final RelNode newViewRelNode = SqlHandlerUtil.resolveNewTableRel(true, createView.getFieldNames(), validatedRowType, queryRelNode); |
| |
| final SchemaPlus defaultSchema = context.getNewDefaultSchema(); |
| final AbstractSchema drillSchema = SchemaUtilities.resolveToMutableDrillSchema(defaultSchema, createView.getSchemaPath()); |
| |
| final View view = new View(newViewName, viewSql, newViewRelNode.getRowType(), |
| SchemaUtilities.getSchemaPathAsList(defaultSchema)); |
| final String schemaPath = drillSchema.getFullSchemaName(); |
| |
| // check view creation possibility |
| if(!checkViewCreationPossibility(drillSchema, createView, context)) { |
| return DirectPlan |
| .createDirectPlan(context, false, String.format("A table or view with given name [%s] already exists in schema [%s]", view.getName(), schemaPath)); |
| } |
| |
| final boolean replaced = drillSchema.createView(view); |
| final String summary = String.format("View '%s' %s successfully in '%s' schema", |
| newViewName, replaced ? "replaced" : "created", drillSchema.getFullSchemaName()); |
| |
| return DirectPlan.createDirectPlan(context, true, summary); |
| } |
| |
| /** |
| * Validates if view can be created in indicated schema: |
| * checks if object (persistent / temporary table) with the same name exists |
| * or if view with the same name exists but replace flag is not set |
| * or if object with the same name exists but if not exists flag is set. |
| * |
| * @param drillSchema schema where views will be created |
| * @param view create view call |
| * @param context query context |
| * @return if view can be created in indicated schema |
| * @throws UserException if view cannot be created in indicated schema and no duplicate check requested |
| */ |
| private boolean checkViewCreationPossibility(AbstractSchema drillSchema, SqlCreateView view, QueryContext context) { |
| final String schemaPath = drillSchema.getFullSchemaName(); |
| final String viewName = view.getName(); |
| final Table table = SqlHandlerUtil.getTableFromSchema(drillSchema, viewName); |
| |
| final boolean isTable = (table != null && table.getJdbcTableType() != Schema.TableType.VIEW) |
| || context.getSession().isTemporaryTable(drillSchema, context.getConfig(), viewName); |
| final boolean isView = (table != null && table.getJdbcTableType() == Schema.TableType.VIEW); |
| |
| switch (view.getSqlCreateType()) { |
| case SIMPLE: |
| if (isTable) { |
| throw UserException |
| .validationError() |
| .message("A non-view table with given name [%s] already exists in schema [%s]", viewName, schemaPath) |
| .build(logger); |
| } else if (isView) { |
| throw UserException |
| .validationError() |
| .message("A view with given name [%s] already exists in schema [%s]", viewName, schemaPath) |
| .build(logger); |
| } |
| break; |
| case OR_REPLACE: |
| if (isTable) { |
| throw UserException |
| .validationError() |
| .message("A non-view table with given name [%s] already exists in schema [%s]", viewName, schemaPath) |
| .build(logger); |
| } |
| break; |
| case IF_NOT_EXISTS: |
| if (isTable || isView) { |
| return false; |
| } |
| break; |
| } |
| return true; |
| } |
| |
| } |
| |
| /** Handler for Drop View [If Exists] DDL command. */ |
| public static class DropView extends ViewHandler { |
| public DropView(SqlHandlerConfig config) { |
| super(config); |
| } |
| |
| @Override |
| public PhysicalPlan getPlan(SqlNode sqlNode) throws IOException, ForemanSetupException { |
| SqlDropView dropView = unwrap(sqlNode, SqlDropView.class); |
| final String viewName = DrillStringUtils.removeLeadingSlash(dropView.getName()); |
| final AbstractSchema drillSchema = |
| SchemaUtilities.resolveToMutableDrillSchema(context.getNewDefaultSchema(), dropView.getSchemaPath()); |
| |
| final String schemaPath = drillSchema.getFullSchemaName(); |
| |
| final Table viewToDrop = SqlHandlerUtil.getTableFromSchema(drillSchema, viewName); |
| if (dropView.checkViewExistence()) { |
| if (viewToDrop == null || viewToDrop.getJdbcTableType() != Schema.TableType.VIEW){ |
| return DirectPlan.createDirectPlan(context, false, |
| String.format("View [%s] not found in schema [%s].", viewName, schemaPath)); |
| } |
| } else { |
| if (viewToDrop != null && viewToDrop.getJdbcTableType() != Schema.TableType.VIEW) { |
| throw UserException.validationError() |
| .message("[%s] is not a VIEW in schema [%s]", viewName, schemaPath) |
| .build(logger); |
| } else if (viewToDrop == null) { |
| throw UserException.validationError() |
| .message("Unknown view [%s] in schema [%s].", viewName, schemaPath) |
| .build(logger); |
| } |
| } |
| |
| SqlHandlerUtil.dropViewFromSchema(drillSchema, viewName); |
| |
| return DirectPlan.createDirectPlan(context, true, |
| String.format("View [%s] deleted successfully from schema [%s].", viewName, schemaPath)); |
| } |
| } |
| } |