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sql-ref-syntax-ddl-create-table-hiveformat.md

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CREATE HIVEFORMAT TABLE
CREATE HIVEFORMAT TABLE
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.

Description

The CREATE TABLE statement defines a new table using Hive format.

Syntax

CREATE [ EXTERNAL ] TABLE [ IF NOT EXISTS ] table_identifier
    [ ( col_name1[:] col_type1 [ COMMENT col_comment1 ], ... ) ]
    [ COMMENT table_comment ]
    [ PARTITIONED BY ( col_name2[:] col_type2 [ COMMENT col_comment2 ], ... ) 
        | ( col_name1, col_name2, ... ) ]
    [ CLUSTERED BY ( col_name1, col_name2, ...) 
        [ SORTED BY ( col_name1 [ ASC | DESC ], col_name2 [ ASC | DESC ], ... ) ] 
        INTO num_buckets BUCKETS ]
    [ ROW FORMAT row_format ]
    [ STORED AS file_format ]
    [ LOCATION path ]
    [ TBLPROPERTIES ( key1=val1, key2=val2, ... ) ]
    [ AS select_statement ]

Note that, the clauses between the columns definition clause and the AS SELECT clause can come in as any order. For example, you can write COMMENT table_comment after TBLPROPERTIES.

Parameters

  • table_identifier

    Specifies a table name, which may be optionally qualified with a database name.

    Syntax: [ database_name. ] table_name

  • EXTERNAL

    Table is defined using the path provided as LOCATION, does not use default location for this table.

  • PARTITIONED BY

    Partitions are created on the table, based on the columns specified.

  • CLUSTERED BY

    Partitions created on the table will be bucketed into fixed buckets based on the column specified for bucketing.

    NOTE: Bucketing is an optimization technique that uses buckets (and bucketing columns) to determine data partitioning and avoid data shuffle.

  • SORTED BY

    Specifies an ordering of bucket columns. Optionally, one can use ASC for an ascending order or DESC for a descending order after any column names in the SORTED BY clause. If not specified, ASC is assumed by default.

  • INTO num_buckets BUCKETS

    Specifies buckets numbers, which is used in CLUSTERED BY clause.

  • row_format

    Specifies the row format for input and output. See HIVE FORMAT for more syntax details.

  • STORED AS

    File format for table storage, could be TEXTFILE, ORC, PARQUET, etc.

  • LOCATION

    Path to the directory where table data is stored, which could be a path on distributed storage like HDFS, etc.

  • COMMENT

    A string literal to describe the table.

  • TBLPROPERTIES

    A list of key-value pairs that is used to tag the table definition.

  • AS select_statement

    The table is populated using the data from the select statement.

Examples

--Use hive format
CREATE TABLE student (id INT, name STRING, age INT) STORED AS ORC;

--Use data from another table
CREATE TABLE student_copy STORED AS ORC
    AS SELECT * FROM student;

--Specify table comment and properties
CREATE TABLE student (id INT, name STRING, age INT)
    COMMENT 'this is a comment'
    STORED AS ORC
    TBLPROPERTIES ('foo'='bar');  

--Specify table comment and properties with different clauses order
CREATE TABLE student (id INT, name STRING, age INT)
    STORED AS ORC
    TBLPROPERTIES ('foo'='bar')
    COMMENT 'this is a comment';

--Create partitioned table
CREATE TABLE student (id INT, name STRING)
    PARTITIONED BY (age INT)
    STORED AS ORC;

--Create partitioned table with different clauses order
CREATE TABLE student (id INT, name STRING)
    STORED AS ORC
    PARTITIONED BY (age INT);

--Use Row Format and file format
CREATE TABLE student (id INT, name STRING)
    ROW FORMAT DELIMITED FIELDS TERMINATED BY ','
    STORED AS TEXTFILE;

--Use complex datatype
CREATE EXTERNAL TABLE family(
        name STRING,
        friends ARRAY<STRING>,
        children MAP<STRING, INT>,
        address STRUCT<street: STRING, city: STRING>
    )
    ROW FORMAT DELIMITED FIELDS TERMINATED BY ',' ESCAPED BY '\\'
    COLLECTION ITEMS TERMINATED BY '_'
    MAP KEYS TERMINATED BY ':'
    LINES TERMINATED BY '\n'
    NULL DEFINED AS 'foonull'
    STORED AS TEXTFILE
    LOCATION '/tmp/family/';

--Use predefined custom SerDe
CREATE TABLE avroExample
    ROW FORMAT SERDE 'org.apache.hadoop.hive.serde2.avro.AvroSerDe'
    STORED AS INPUTFORMAT 'org.apache.hadoop.hive.ql.io.avro.AvroContainerInputFormat'
        OUTPUTFORMAT 'org.apache.hadoop.hive.ql.io.avro.AvroContainerOutputFormat'
    TBLPROPERTIES ('avro.schema.literal'='{ "namespace": "org.apache.hive",
        "name": "first_schema",
        "type": "record",
        "fields": [
                { "name":"string1", "type":"string" },
                { "name":"string2", "type":"string" }
            ] }');

--Use personalized custom SerDe(we may need to `ADD JAR xxx.jar` first to ensure we can find the serde_class,
--or you may run into `CLASSNOTFOUND` exception)
ADD JAR /tmp/hive_serde_example.jar;

CREATE EXTERNAL TABLE family (id INT, name STRING)
    ROW FORMAT SERDE 'com.ly.spark.serde.SerDeExample'
    STORED AS INPUTFORMAT 'com.ly.spark.example.serde.io.SerDeExampleInputFormat'
        OUTPUTFORMAT 'com.ly.spark.example.serde.io.SerDeExampleOutputFormat'
    LOCATION '/tmp/family/';

--Use `CLUSTERED BY` clause to create bucket table without `SORTED BY`
CREATE TABLE clustered_by_test1 (ID INT, AGE STRING)
    CLUSTERED BY (ID)
    INTO 4 BUCKETS
    STORED AS ORC;

--Use `CLUSTERED BY` clause to create bucket table with `SORTED BY`
CREATE TABLE clustered_by_test2 (ID INT, NAME STRING)
    PARTITIONED BY (YEAR STRING)
    CLUSTERED BY (ID, NAME)
    SORTED BY (ID ASC)
    INTO 3 BUCKETS
    STORED AS PARQUET;

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