SQLite
概述
SQLite是一个进程内的库,实现了自给自足的、无服务器的、零配置的、事务性的 SQL 数据库引擎。它是一个零配置的数据库,这意味着与其它数据库不同,不需要在系统中配置。 就像其它数据库,SQLite引擎不是一个独立的进程,可以按应用程序需求进行静态或动态连接。SQLite直接访问其存储文件。
SQLite语法
语法是一组独特的规则和约定。 以下是SQLite的语法列表。
区分大小写:
- SQLite不区分大小写。但是,有一些区分大小写的命令。例如:GLOB和glob在SQLite语句中有不同的含义。
注释:
- 注释用于在SQLite代码中增加代码的可读性。
- 注释不能嵌套。
- 注释以两个连续的“ - ”字符。
- 也可使用“/”字符开始,并延伸至下一个“/”字符对所包括的内容视为注释。
SQLite语句
所有的SQLite语句都是以关键字(如:SELECT,INSERT,UPDATE,DELETE,ALTER,DROP等)开始的。所有语句都以分号(;)结尾。
SQLite ANALYZE语句的语法:
ANALYZE;
-- or
ANALYZE database_name;
-- or
ANALYZE database_name.table_name;
SQLite AND/OR子句的语法:
SELECT column1, column2....columnN
FROM table_name
WHERE CONDITION-1 {AND|OR} CONDITION-2;
SQLite ALTER TABLE语句的语法
ALTER TABLE table_name ADD COLUMN column_def...;
SQLite ALTER TABLE语句(Rename)语句的语法
ALTER TABLE table_name RENAME TO new_table_name;
SQLite ATTACH DATABASE语句的语法:
ATTACH DATABASE 'DatabaseName' As 'Alias-Name';
SQLite BEGIN TRANSACTION语句的语法:
BEGIN;
-- or
BEGIN EXCLUSIVE TRANSACTION;
SQLite BETWEEN语句的语法:
SELECT column1, column2....columnN
FROM table_name
WHERE column_name BETWEEN val-1 AND val-2;
SQLite COMMIT Statement:
COMMIT;
SQLite CREATE INDEX语句的语法:
CREATE INDEX index_name
ON table_name ( column_name COLLATE NOCASE );
SQLite CREATE UNIQUE INDEX语句的语法:
CREATE UNIQUE INDEX index_name
ON table_name ( column1, column2,...columnN);
SQLite CREATE TABLE语句的语法:
CREATE TABLE table_name(
column1 datatype,
column2 datatype,
column3 datatype,
.....
columnN datatype,
PRIMARY KEY( one or more columns ));
SQLite CREATE TRIGGER语句的语法:
CREATE TRIGGER database_name.trigger_name
BEFORE INSERT ON table_name FOR EACH ROW
BEGIN
stmt1;
stmt2;
....
END;
SQLite CREATE VIEW语句的语法:
CREATE VIEW database_name.view_name AS
SELECT statement....;
SQLite CREATE VIRTUAL TABLE语句的语法:
CREATE VIRTUAL TABLE database_name.table_name USING weblog( access.log );
-- or
CREATE VIRTUAL TABLE database_name.table_name USING fts3( );
SQLite COMMIT TRANSACTION语句的语法:
COMMIT;
SQLite COUNT语句的语法:
SELECT COUNT(column_name)
FROM table_name
WHERE CONDITION;
SQLite DELETE语句的语法:
DELETE FROM table_name
WHERE {CONDITION};
SQLite DETACH DATABASE语句的语法:
DETACH DATABASE 'Alias-Name';
SQLite DISTINCT语句的语法:
SELECT DISTINCT column1, column2....columnN
FROM table_name;
SQLite DROP INDEX语句的语法:
DROP INDEX database_name.index_name;
SQLite DROP TABLE语句的语法:
DROP TABLE database_name.table_name;
SQLite DROP VIEW语句的语法:
DROP INDEX database_name.view_name;
SQLite DROP TRIGGER 语句的语法:
DROP INDEX database_name.trigger_name;
SQLite EXISTS语句的语法:
SELECT column1, column2....columnN
FROM table_name
WHERE column_name EXISTS (SELECT * FROM table_name );
SQLite EXPLAIN语句的语法:
EXPLAIN INSERT statement...;
-- or
EXPLAIN QUERY PLAN SELECT statement...;
SQLite GLOB语句的语法:
SELECT column1, column2....columnN
FROM table_name
WHERE column_name GLOB { PATTERN };
SQLite GROUP BY语句的语法:
SELECT SUM(column_name)
FROM table_name
WHERE CONDITION
GROUP BY column_name;
SQLite HAVING语句的语法:
SELECT SUM(column_name)
FROM table_name
WHERE CONDITION
GROUP BY column_name
HAVING (arithematic function condition);
SQLite INSERT INTO语句的语法:
INSERT INTO table_name( column1, column2....columnN)
VALUES ( value1, value2....valueN);
SQLite IN语句的语法:
SELECT column1, column2....columnN
FROM table_name
WHERE column_name IN (val-1, val-2,...val-N);
SQLite Like语句的语法:
SELECT column1, column2....columnN
FROM table_name
WHERE column_name LIKE { PATTERN };
SQLite NOT IN语句的语法:
SELECT column1, column2....columnN
FROM table_name
WHERE column_name NOT IN (val-1, val-2,...val-N);
SQLite ORDER BY语句的语法:
SELECT column1, column2....columnN
FROM table_name
WHERE CONDITION
ORDER BY column_name {ASC|DESC};
SQLite PRAGMA语句的语法:
PRAGMA pragma_name;
有关pragma的几个示例:
PRAGMA page_size;
PRAGMA cache_size = 1024;
PRAGMA table_info(table_name);
SQLite RELEASE SAVEPOINT语句的语法:
RELEASE savepoint_name;
SQLite REINDEX语句的语法:
REINDEX collation_name;
REINDEX database_name.index_name;
REINDEX database_name.table_name;
SQLite ROLLBACK语句的语法:
ROLLBACK;
-- or
ROLLBACK TO SAVEPOINT savepoint_name;
SQLite SAVEPOINT语句的语法:
SAVEPOINT savepoint_name;
SQLite SELECT语句的语法:
SELECT column1, column2....columnN
FROM table_name;
SQLite UPDATE语句的语法:
UPDATE table_name
SET column1 = value1, column2 = value2....columnN=valueN
[ WHERE CONDITION ];
SQLite VACUUM语句的语法:
VACUUM;
SQLite WHERE Clause:
SELECT column1, column2....columnN
FROM table_name
WHERE CONDITION;