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Doris常见SQL语法说明

MAPREDUCE服务 MRS-CREATE TABLE:使用示例

使用示例创建一个名为table1的普通表： CREATE TABLE example_db.table1 ( k1 TINYINT, k2 DECIMAL(10, 2) DEFAULT "10.5", k3 CHAR(10) COMMENT "string column", k4 INT NOT NULL DEFAULT "1" COMMENT "int column" ) COMMENT "table comment" DISTRIBUTED BY HASH(k1) BUCKETS 32; 创建一个名为table2的分区表。使用event_day列作为分区列，建立3个分区：p201706、p201707、p201708，取值为： p201706：范围为[最小值, 2017-07-01) p201707：范围为[2017-07-01, 2017-08-01) p201708：范围为[2017-08-01, 2017-09-01) 每个分区使用siteid进行哈希分桶，桶数为10。创建表命令如下： CREATE TABLE table2 ( event_day DATE, siteid INT DEFAULT '10', citycode SMALLINT, username VARCHAR(32) DEFAULT '', pv BIGINT SUM DEFAULT '0' ) AGGREGATE KEY(event_day, siteid, citycode, username) PARTITION BY RANGE(event_day) ( PARTITION p201706 VALUES LESS THAN ('2017-07-01'), PARTITION p201707 VALUES LESS THAN ('2017-08-01'), PARTITION p201708 VALUES LESS THAN ('2017-09-01') ) DISTRIBUTED BY HASH(siteid) BUCKETS 10 PROPERTIES("replication_num" = "2"); Doris创建表时限制至少指定2副本，以保证高可用。可以对Table增加上卷表（Rollup）以提高查询性能。表的列的Null属性默认为true，会对查询性能有一定的影响。 Doris表必须指定分桶列。查看表内容： SHOW TABLES; +----------------------+ | Tables_in_example_db | +----------------------+ | table1 | | table2 | +----------------------+ 2 rows in set (0.01 sec) DESC table1; +----------+-------------+------+-------+---------+-------+ | Field | Type | Null | Key | Default | Extra | +----------+-------------+------+-------+---------+-------+ | siteid | int(11) | Yes | true | 10 | | | citycode | smallint(6) | Yes | true | N/A | | | username | varchar(32) | Yes | true | | | | pv | bigint(20) | Yes | false | 0 | SUM | +----------+-------------+------+-------+---------+-------+ 4 rows in set (0.00 sec) DESC table2; +-----------+-------------+------+-------+---------+-------+ | Field | Type | Null | Key | Default | Extra | +-----------+-------------+------+-------+---------+-------+ | event_day | date | Yes | true | N/A | | | siteid | int(11) | Yes | true | 10 | | | citycode | smallint(6) | Yes | true | N/A | | | username | varchar(32) | Yes | true | | | | pv | bigint(20) | Yes | false | 0 | SUM | +-----------+-------------+------+-------+---------+-------+ 5 rows in set (0.00 sec)

MAPREDUCE服务 MRS Doris常见SQL语法说明
MAPREDUCE服务 MRS-CREATE TABLE:基本语法

基本语法 CREATE TABLE [IF NOT EXISTS] [database.]table ( column_definition_list, [index_definition_list] ) [engine_type] [keys_type] [table_comment] [partition_info] distribution_desc [rollup_list] [properties] [extra_properties]

MAPREDUCE服务 MRS Doris常见SQL语法说明