[ 
https://issues.apache.org/jira/browse/DRILL-4514?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15206070#comment-15206070
 ] 

ASF GitHub Bot commented on DRILL-4514:
---------------------------------------

Github user arina-ielchiieva commented on a diff in the pull request:

    https://github.com/apache/drill/pull/436#discussion_r56957772
  
    --- Diff: 
exec/java-exec/src/main/java/org/apache/drill/exec/planner/sql/parser/SqlDescribeSchema.java
 ---
    @@ -0,0 +1,82 @@
    +/**
    + * 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
    + * <p/>
    + * http://www.apache.org/licenses/LICENSE-2.0
    + * <p/>
    + * 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.parser;
    +
    +import org.apache.calcite.sql.SqlCall;
    +import org.apache.calcite.sql.SqlIdentifier;
    +import org.apache.calcite.sql.SqlKind;
    +import org.apache.calcite.sql.SqlLiteral;
    +import org.apache.calcite.sql.SqlNode;
    +import org.apache.calcite.sql.SqlOperator;
    +import org.apache.calcite.sql.SqlSpecialOperator;
    +import org.apache.calcite.sql.SqlWriter;
    +import org.apache.calcite.sql.parser.SqlParserPos;
    +import org.apache.drill.exec.planner.sql.handlers.AbstractSqlHandler;
    +import org.apache.drill.exec.planner.sql.handlers.DescribeSchemaHandler;
    +import org.apache.drill.exec.planner.sql.handlers.SqlHandlerConfig;
    +
    +import java.util.Collections;
    +import java.util.List;
    +
    +/**
    + * Sql parse tree node to represent statement:
    + * SHOW FILES [{FROM | IN} db_name] [LIKE 'pattern' | WHERE expr]
    + */
    +public class SqlDescribeSchema extends DrillSqlCall {
    +
    +  private final SqlIdentifier schema;
    +
    +  public static final SqlSpecialOperator OPERATOR =
    +      new SqlSpecialOperator("DESCRIBE_SCHEMA", SqlKind.OTHER) {
    +        @Override
    +        public SqlCall createCall(SqlLiteral functionQualifier, 
SqlParserPos pos, SqlNode... operands) {
    +          return new SqlDescribeSchema(pos, (SqlIdentifier) operands[0]);
    +        }
    +      };
    +
    +  public SqlDescribeSchema(SqlParserPos pos, SqlIdentifier schema) {
    +    super(pos);
    +    this.schema = schema;
    +    assert schema != null;
    --- End diff --
    
    Agree, preconditions is better. But I have checked that schema can't come 
as null, so I have removed check for not null at all.


> Add describe schema <schema_name> command
> -----------------------------------------
>
>                 Key: DRILL-4514
>                 URL: https://issues.apache.org/jira/browse/DRILL-4514
>             Project: Apache Drill
>          Issue Type: New Feature
>    Affects Versions: Future
>            Reporter: Arina Ielchiieva
>            Assignee: Arina Ielchiieva
>
> Add describe database <db_name> command which will return directory 
> associated with a database on the fly.
> Syntax:
> describe database <db_name>
> describe schema <schema_name>
> Output:
> {noformat}
>  DESCRIBE SCHEMA xdf.proc;
> +---------------------+----------------------------+
> |    name             | location                   |
> +---------------------+----------------------------+
> | xdf.proc            | maprfs://dl.data/processed |
> +---------------------+----------------------------+
> {noformat}
> Current implementation covers only dfs schema.
> For all other "<INFORMATION UNAVAILABLE>" will be returned.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

Reply via email to