结构定义 |
CREATE TABLE |
创建新表。 语法:@H_502_22@
sql-command::= |
CREATE [TEMP | TEMPORARY] TABLE table-name (@H_502_22@column-def [, column-def]*@H_502_22@[, constraint]*@H_502_22@) |
sql-command::= |
CREATE [TEMP | TEMPORARY] TABLE [database-name.] table-name AS select-statement |
column-def::= |
name [type] [[CONSTRAINT name] column-constraint]* |
type::= |
typename |@H_502_22@typename ( number ) |@H_502_22@typename ( number , number ) |
column-constraint::= |
NOT NULL [ conflict-clause ] |@H_502_22@PRIMARY KEY [sort-order] [ conflict-clause ] |@H_502_22@UNIQUE [ conflict-clause ] |@H_502_22@CHECK ( expr ) [ conflict-clause ] |@H_502_22@DEFAULT value |@H_502_22@COLLATE collation-name |
constraint::= |
PRIMARY KEY ( column-list ) [ conflict-clause ] |@H_502_22@UNIQUE ( column-list ) [ conflict-clause ] |@H_502_22@CHECK ( expr ) [ conflict-clause ] |
conflict-clause::= |
ON CONFLICT conflict-algorithm |
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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:@H_502_22@
sql-command::= |
CREATE [TEMP | TEMPORARY] VIEW [database-name.] view-name AS select-statement |
@H_502_22@例子:@H_502_22@CREATE VIEW master_view AS@H_502_22@ SELECT * FROM sqlite_master WHERE type='view';@H_502_22@说明:@H_502_22@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:@H_502_22@
sql-statement::= |
CREATE [TEMP | TEMPORARY] TRIGGER trigger-name [ BEFORE | AFTER ]@H_502_22@database-event ON [database-name .] table-name@H_502_22@trigger-action |
sql-statement::= |
CREATE [TEMP | TEMPORARY] TRIGGER trigger-name INSTEAD OF@H_502_22@database-event ON [database-name .] view-name@H_502_22@trigger-action |
database-event::= |
DELETE | @H_502_22@INSERT | @H_502_22@UPDATE | @H_502_22@UPDATE OF column-list |
trigger-action::= |
[ FOR EACH ROW | FOR EACH STATEMENT ] [ WHEN expression ] @H_502_22@BEGIN @H_502_22@trigger-step ; [ trigger-step ; ]*@H_502_22@END |
trigger-step::= |
update-statement | insert-statement | @H_502_22@delete-statement | select-statement |
例子:@H_502_22@CREATE TRIGGER update_customer_address UPDATE OF address ON customers @H_502_22@ BEGIN@H_502_22@ UPDATE orders SET address = new.address WHERE customer_name = old.name;@H_502_22@ END;@H_502_22@说明:@H_502_22@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。@H_502_22@比如执行如下一条语句:@H_502_22@UPDATE customers SET address = '1 Main St.' WHERE name = 'Jack Jones';@H_502_22@数据库将自动执行如下语句:@H_502_22@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:@H_502_22@
sql-statement::= |
CREATE [UNIQUE] INDEX index-name @H_502_22@ON [database-name .] table-name ( column-name [, column-name]* )@H_502_22@[ ON CONFLICT conflict-algorithm ] |
column-name::= |
name [ COLLATE collation-name] [ ASC | DESC ] |
例子:@H_502_22@CREATE INDEXidx_email ON customers (email);@H_502_22@说明:@H_502_22@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:@H_502_22@
sql-command::= |
DROP TABLE [database-name.] table-name |
例子:@H_502_22@DROP TABLE customers; |
DROP VIEW |
删除一个视图。 语法:@H_502_22@
sql-command::= |
DROP VIEW view-name |
例子:@H_502_22@DROP VIEW master_view; |
DROP TRIGGER |
删除一个触发器。 语法:@H_502_22@
sql-statement::= |
DROP TRIGGER [database-name .] trigger-name |
例子:@H_502_22@DROP TRIGGER update_customer_address; |
DROP INDEX |
删除一个索引。 语法:@H_502_22@
sql-command::= |
DROP INDEX [database-name .] index-name |
例子:@H_502_22@DROP INDEX idx_email; |
数据操作 |
INSERT |
将新行插入到表。 语法:@H_502_22@
sql-statement::= |
INSERT [OR conflict-algorithm] INTO [database-name .] table-name [(column-list)] VALUES(value-list) |@H_502_22@INSERT [OR conflict-algorithm] INTO [database-name .] table-name [(column-list)] select-statement |
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UPDATE |
更新表中的现有数据。 语法:@H_502_22@
sql-statement::= |
UPDATE [ OR conflict-algorithm ] [database-name .] table-name@H_502_22@SET assignment [, assignment]*@H_502_22@[WHERE expr] |
assignment::= |
column-name = expr |
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DELETE |
从表中删除行。 语法:@H_502_22@
sql-statement::= |
DELETE FROM [database-name .] table-name [WHERE expr] |
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SELECT |
从表中检索数据。 语法:@H_502_22@
sql-statement::= |
SELECT [ALL | DISTINCT] result [FROM table-list]@H_502_22@[WHERE expr]@H_502_22@[GROUP BY expr-list]@H_502_22@[HAVING expr]@H_502_22@[compound-op select]*@H_502_22@[ORDER BY sort-expr-list]@H_502_22@[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] |@H_502_22@( 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:@H_502_22@
sql-statement::= |
REPLACE INTO [database-name .] table-name [( column-list )] VALUES ( value-list ) |@H_502_22@REPLACE INTO [database-name .] table-name [( column-list )] select-statement |
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事务处理 |
BEGIN TRANSACTION |
标记一个事务的起始点。 语法:@H_502_22@
sql-statement::= |
BEGIN [TRANSACTION [name]] |
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END TRANSACTION |
标记一个事务的终止。 语法:@H_502_22@
sql-statement::= |
END [TRANSACTION [name]] |
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COMMIT TRANSACTION |
标志一个事务的结束。 语法:@H_502_22@
sql-statement::= |
COMMIT [TRANSACTION [name]] |
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ROLLBACK TRANSACTION |
将事务回滚到事务的起点。 语法:@H_502_22@
sql-statement::= |
ROLLBACK [TRANSACTION [name]] |
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其他操作 |
COPY |
主要用于导入大量的数据。 语法:@H_502_22@
sql-statement::= |
COPY [ OR conflict-algorithm ] [database-name .] table-name FROM filename@H_502_22@[ USING DELIMITERS delim ] |
例子:@H_502_22@COPYcustomers FROM customers.csv; |
EXPLAIN |
语法:@H_502_22@
sql-statement::= |
EXPLAIN sql-statement |
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PRAGMA |
语法:@H_502_22@
sql-statement::= |
PRAGMA name [= value] |@H_502_22@PRAGMA function(arg) |
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VACUUM |
语法:@H_502_22@
sql-statement::= |
VACUUM [index-or-table-name] |
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ATTACH DATABASE |
附加一个数据库到当前的数据库连接。 语法:@H_502_22@
sql-statement::= |
ATTACH [DATABASE] database-filename AS database-name |
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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:@H_502_22@
sql-command::= |
DETACH [DATABASE] database-name |
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