查看 SQL 语句
查看所有 SQL 语句
用户可以在任何 KWDB 客户端使用 \h 命令查看 KWDB 支持的所有 SQL 语句及相关描述。
\h;
执行成功后，控制台输出以下信息：
Configuration:
DISCARD reset the session to its initial state
RESET reset a session variable to its default value
RESET CLUSTER SETTING reset a cluster setting to its default value
SET CLUSTER SETTING change a cluster setting
SET SESSION change a session variable
SHOW CLUSTER SETTING display cluster settings
SHOW SAVEPOINT display current savepoint properties
SHOW SESSION display session variables
SHOW TRANSACTION display current transaction properties
USE set the current database
Data Manipulation:
<SELECTCLAUSE> access tabular data
<SOURCE> define a data source for SELECT
DELETE delete rows from a table
EXPORT export data to file in a distributed manner
IMPORT load data from file in a distributed manner
INSERT create new rows in a table
SELECT retrieve rows from a data source and compute a result
TABLE select an entire table
TRUNCATE empty one or more tables
UPDATE update rows of a table
UPSERT create or replace rows in a table
VALUES select a given set of values
Experimental:
SHOW HISTOGRAM display histogram (experimental)
SHOW STATISTICS display table statistics (experimental)
Miscellaneous:
CANCEL JOBS cancel background jobs
CANCEL QUERIES cancel running queries
CANCEL SESSIONS cancel open sessions
CREATE STATISTICS create a new table statistic
DEALLOCATE remove a prepared statement
EXECUTE execute a statement prepared previously
EXPLAIN show the logical plan of a query
PAUSE JOBS pause background jobs
PAUSE SCHEDULE pause specified scheduled job
PREPARE prepare a statement for later execution
RESUME JOBS resume background jobs
RESUME SCHEDULE resume background scheduled job
SHOW APPLICATIONS list open client applications
SHOW JOBS list background jobs
SHOW QUERIES list running queries
SHOW RANGE show range information for a row
SHOW RANGES list ranges
SHOW SESSIONS list open client sessions
SHOW SYNTAX analyze SQL syntax
SHOW TRACE display an execution trace
Privileges And Security:
ALTER ROLE alter a role
CREATE ROLE define a new role
DROP ROLE remove a user
GRANT define access privileges and role memberships
REVOKE remove access privileges and role memberships
SHOW GRANTS list grants
SHOW ROLES list defined roles
SHOW USERS list defined users
Schema Manipulation:
ALTER AUDIT change the definition of an audit
ALTER DATABASE change the definition of a database
ALTER INDEX change the definition of an index
ALTER RANGE change the parameters of a range
ALTER SCHEDULE change the definition of a schedule
ALTER SEQUENCE change the definition of a sequence
ALTER TABLE change the definition of a table
ALTER VIEW change the definition of a view
CREATE AUDIT create an audit
CREATE DATABASE create a new database
CREATE FUNCTION create a new function
CREATE INDEX create a new index
CREATE SCHEMA create a new schema
CREATE SEQUENCE create a new sequence
CREATE TABLE create a new table
CREATE TS DATABASE create a new timeseries database
CREATE VIEW create a new view
DROP AUDIT remove an audit
DROP DATABASE remove a database
DROP FUNCTION remove a function
DROP INDEX remove an index
DROP SCHEMA remove a schema
DROP SEQUENCE remove a sequence
DROP TABLE remove a table
DROP VIEW remove a view
SHOW ATTRIBUTES list the attributes of the timeseries table
SHOW AUDITS list audit policies
SHOW COLUMNS list columns in relation
SHOW CONSTRAINTS list constraints
SHOW CREATE display the CREATE statement for a table, sequence or view
SHOW DATABASES list databases
SHOW FUNCTION Show the details of the function
SHOW FUNCTIONS list functions
SHOW INDEXES list indexes
SHOW RETENTIONS list retentions of the timeseries table
SHOW SCHEDULE show schedule details
SHOW SCHEDULES list schedules
SHOW SCHEMAS list schemas
SHOW SEQUENCES list sequences
SHOW TABLES list tables
Transaction Control:
BEGIN start a transaction
COMMIT commit the current transaction
RELEASE complete a sub-transaction
ROLLBACK abort the current (sub-)transaction
SAVEPOINT start a sub-transaction
SET TRANSACTION configure the transaction settings
如果系统无法找到匹配的字符串，控制台输出以下信息：
no help available for "<sql statement>".
Try \h with no argument to see available help.
使用关键字查看 SQL 语句
用户也可以使用关键字查看某一类的 SQL 语句。
以下示例使用 SHOW 关键字查看 KWDB 支持的所有 SHOW 语句。
\h SHOW;
执行成功后，控制台输出以下信息：
Command: SHOW
Syntax:
SHOW APPLICATIONS, SHOW BACKUP, SHOW CLUSTER SETTING, SHOW COLUMNS,
SHOW CONSTRAINTS, SHOW CREATE, SHOW CREATE DATABASE, SHOW DATABASES, SHOW HISTOGRAM, SHOW INDEXES,
SHOW PARTITIONS, SHOW JOBS, SHOW QUERIES, SHOW RANGE, SHOW RANGES,
SHOW ROLES, SHOW SCHEMAS, SHOW SEQUENCES, SHOW SESSION, SHOW SESSIONS,
SHOW STATISTICS, SHOW SYNTAX, SHOW TABLES, SHOW TRACE SHOW TRANSACTION, SHOW USERS
查看特定 SQL 语句的帮助信息
用户可以在指定 SQL 语句前使用 \h 命令，查看对应 SQL 语句的帮助信息。系统返回特定 SQL 语句的具体帮助信息，包括：Command、Description、Category、Syntax、See also 等。
Command：SQL 语句Description：SQL 语句的描述信息Category：SQL 语句所属类别Syntax：SQL 语句的句法结构See Also：与指定 SQL 语句相关的其他 SQL 语句
以下示例查看 CREATE AUDIT 语句的帮助信息。
\h CREATE AUDIT;
执行成功后，控制台输出以下信息：
Description: create a AUDIT
Category: schema manipulation
Syntax:
--Object Audit
CREATE AUDIT <audit_name> ON <TargetType> target_name
FOR [ Oprations, ...] TO [username]
[ WITH <option> [= <value>] [, ...] ]
[ ACTION ...]
[ LEVEL ]
--Stmt Audit
CREATE AUDIT <audit_name> ON <TargetType>
FOR [ Oprations, ...] TO [username]
[ WITH <option> [= <value>] [, ...] ]
[ ACTION ...]
[ LEVEL ]
--Stmt TargetType:
DATABASE, SCHEMA, TABLE, INDEX, VIEW, SEQUENCE,
PROCEDURE, FUNCTION, TRIGGER, CDC, JOB, USER,
ROLE, PRIVILEGE, QUERY, TRANSACTION, SAVEPOINT,
RANGE, STATISTICS, SESSION, SCHEDULE, AUDIT
--Object TargetType:
TABLE, VIEW, COLUMN, FUNCTION
See also:
ALTER AUDIT
DROP AUDIT
SHOW AUDITS