结构定义 |
CREATE TABLE |
创建新表。
语法:
sql-command ::= | CREATE [TEMP | TEMPORARY] TABLE table-name (
column-def [, column-def]*
[, constraint]*
) | sql-command ::= | CREATE [TEMP | TEMPORARY] TABLE [database-name.] table-name AS select-statement | column-def ::= | name [type] [[CONSTRAINT name] column-constraint]* | type ::= | typename |
typename ( number ) |
typename ( number , number ) | column-constraint ::= | NOT NULL [ conflict-clause ] |
PRIMARY KEY [sort-order] [ conflict-clause ] |
UNIQUE [ conflict-clause ] |
CHECK ( expr ) [ conflict-clause ] |
DEFAULT value |
COLLATE collation-name | constraint ::= | PRIMARY KEY ( column-list ) [ conflict-clause ] |
UNIQUE ( column-list ) [ conflict-clause ] |
CHECK ( expr ) [ conflict-clause ] | conflict-clause ::= | ON CONFLICT conflict-algorithm |
|
CREATE VIEW |
创建一个视图(虚拟表),该表以另一种方式表示一个或多个表中的数据。
语法:
sql-command ::= | CREATE [TEMP | TEMPORARY] VIEW [database-name.] view-name AS select-statement |
例子:
CREATE VIEW master_view AS
SELECT * FROM sqlite_master WHERE type='view';
说明:
创建一个名为master_view的视图,其中包括sqlite_master这个表中的所有视图表。 |
CREATE TRIGGER |
创建触发器,触发器是一种特殊的存储过程,在用户试图对指定的表执行指定的数据修改语句时自动执行。
语法:
sql-statement ::= | CREATE [TEMP | TEMPORARY] TRIGGER trigger-name [ BEFORE | AFTER ]
database-event ON [database-name .] table-name
trigger-action |
sql-statement ::= | CREATE [TEMP | TEMPORARY] TRIGGER trigger-name INSTEAD OF
database-event ON [database-name .] view-name
trigger-action |
database-event ::= | DELETE |
INSERT |
UPDATE |
UPDATE OF column-list |
trigger-action ::= | [ FOR EACH ROW | FOR EACH STATEMENT ] [ WHEN expression ]
BEGIN
trigger-step ; [ trigger-step ; ]*
END |
trigger-step ::= | update-statement | insert-statement |
delete-statement | select-statement |
例子:
CREATE TRIGGER update_customer_address UPDATE OF address ON customers
BEGIN
UPDATE orders SET address = new.address WHERE customer_name = old.name;
END;
说明:
创建了一个名为update_customer_address的触发器,当用户更新customers表中的address字段时,将触发并更新orders表中的address字段为新的值。
比如执行如下一条语句:
UPDATE customers SET address = '1 Main St.' WHERE name = 'Jack Jones';
数据库将自动执行如下语句:
UPDATE orders SET address = '1 Main St.' WHERE customer_name = 'Jack Jones'; |
CREATE INDEX |
为给定表或视图创建索引。
语法:
sql-statement ::= | CREATE [UNIQUE] INDEX index-name
ON [database-name .] table-name ( column-name [, column-name]* )
[ ON CONFLICT conflict-algorithm ] | column-name ::= | name [ COLLATE collation-name] [ ASC | DESC ] |
例子:
CREATE INDEX idx_email ON customers (email);
说明:
为customers表中的email创建一个名为idx_email的字段。 |
结构删除 |
DROP TABLE |
删除表定义及该表的所有索引。
语法:
sql-command ::= | DROP TABLE [database-name.] table-name | 例子:
DROP TABLE customers; |
DROP VIEW |
删除一个视图。
语法:
sql-command ::= | DROP VIEW view-name |
例子:
DROP VIEW master_view; |
DROP TRIGGER |
删除一个触发器。
语法:
sql-statement ::= | DROP TRIGGER [database-name .] trigger-name |
例子:
DROP TRIGGER update_customer_address; |
DROP INDEX |
删除一个索引。
语法:
sql-command ::= | DROP INDEX [database-name .] index-name |
例子:
DROP INDEX idx_email; |
数据操作 |
INSERT |
将新行插入到表。
语法:
sql-statement ::= | INSERT [OR conflict-algorithm] INTO [database-name .] table-name [(column-list)] VALUES(value-list) |
INSERT [OR conflict-algorithm] INTO [database-name .] table-name [(column-list)] select-statement |
|
UPDATE |
更新表中的现有数据。
语法:
sql-statement ::= | UPDATE [ OR conflict-algorithm ] [database-name .] table-name
SET assignment [, assignment]*
[WHERE expr] | assignment ::= | column-name = expr |
|
DELETE |
从表中删除行。
语法:
sql-statement ::= | DELETE FROM [database-name .] table-name [WHERE expr] |
|
SELECT |
从表中检索数据。
语法:
sql-statement ::= | SELECT [ALL | DISTINCT] result [FROM table-list]
[WHERE expr]
[GROUP BY expr-list]
[HAVING expr]
[compound-op select]*
[ORDER BY sort-expr-list]
[LIMIT integer [( OFFSET | , ) integer]] | result ::= | result-column [, result-column]* | result-column ::= | * | table-name . * | expr [ [AS] string ] | table-list ::= | table [join-op table join-args]* | table ::= | table-name [AS alias] |
( select ) [AS alias] | join-op ::= | , | [NATURAL] [LEFT | RIGHT | FULL] [OUTER | INNER | CROSS] JOIN | join-args ::= | [ON expr] [USING ( id-list )] | sort-expr-list ::= | expr [sort-order] [, expr [sort-order]]* | sort-order ::= | [ COLLATE collation-name ] [ ASC | DESC ] | compound_op ::= | UNION | UNION ALL | INTERSECT | EXCEPT |
|
REPLACE |
类似INSERT
语法:
sql-statement ::= | REPLACE INTO [database-name .] table-name [( column-list )] VALUES ( value-list ) |
REPLACE INTO [database-name .] table-name [( column-list )] select-statement |
|
事务处理 |
BEGIN TRANSACTION |
标记一个事务的起始点。
语法:
sql-statement ::= | BEGIN [TRANSACTION [name]] |
|
END TRANSACTION |
标记一个事务的终止。
语法:
sql-statement ::= | END [TRANSACTION [name]] |
|
COMMIT TRANSACTION |
标志一个事务的结束。
语法:
sql-statement ::= | COMMIT [TRANSACTION [name]] |
|
ROLLBACK TRANSACTION |
将事务回滚到事务的起点。
语法:
sql-statement ::= | ROLLBACK [TRANSACTION [name]] |
|
其他操作 |
COPY |
主要用于导入大量的数据。
语法:
sql-statement ::= | COPY [ OR conflict-algorithm ] [database-name .] table-name FROM filename
[ USING DELIMITERS delim ] | 例子:
COPY customers FROM customers.csv; |
EXPLAIN |
语法:
sql-statement ::= | EXPLAIN sql-statement |
|
PRAGMA |
语法:
sql-statement ::= | PRAGMA name [= value] |
PRAGMA function(arg) |
|
VACUUM |
语法:
sql-statement ::= | VACUUM [index-or-table-name] |
|
ATTACH DATABASE |
附加一个数据库到当前的数据库连接。
语法:
sql-statement ::= | ATTACH [DATABASE] database-filename AS database-name |
|
DETTACH DATABASE |
从当前的数据库分离一个使用ATTACH DATABASE附加的数据库。
语法:
sql-command ::= | DETACH [DATABASE] database-name |
|