Data Definition Language¶

CREATE DATABASE¶

Synopsis

CREATE DATABASE [IF NOT EXISTS] <database_name>

IF NOT EXISTS allows CREATE DATABASE statement to avoid an error which occurs when the database exists.

DROP DATABASE¶

Synopsis

DROP DATABASE [IF EXISTS] <database_name>

IF EXISTS allows DROP DATABASE statement to avoid an error which occurs when the database does not exist.

CREATE TABLE¶

Synopsis

CREATE TABLE [IF NOT EXISTS] <table_name> [(<column_name> <data_type>, ... )]
[using <storage_type> [with (<key> = <value>, ...)]] [AS <select_statement>]

CREATE EXTERNAL TABLE [IF NOT EXISTS] <table_name> (<column_name> <data_type>, ... )
using <storage_type> [with (<key> = <value>, ...)] LOCATION '<path>'

IF NOT EXISTS allows CREATE [EXTERNAL] TABLE statement to avoid an error which occurs when the table does not exist.

create EXTERNAL table lineitem (
L_ORDERKEY bigint,
L_PARTKEY bigint,
...
L_COMMENT text)

USING TEXT WITH ('text.delimiter'='|','compression.codec'='org.apache.hadoop.io.compress.DeflateCodec')
LOCATION 'hdfs://localhost:9010/tajo/warehouse/lineitem_100_snappy';

DROP TABLE¶

Synopsis

DROP TABLE [IF EXISTS] <table_name> [PURGE]

IF EXISTS allows DROP DATABASE statement to avoid an error which occurs when the database does not exist. DROP TABLE statement removes a table from Tajo catalog, but it does not remove the contents. If PURGE option is given, DROP TABLE statement will eliminate the entry in the catalog as well as the contents.

CREATE INDEX¶

Synopsis

CREATE INDEX [ name ] ON table_name [ USING method ]
( { column_name | ( expression ) } [ ASC | DESC ] [ NULLS { FIRST | LAST } ] [, ...] )
[ WHERE predicate ]

DROP INDEX¶

Synopsis

DROP INDEX name