** Various scripts scan this source file in order to generate HTML ** documentation, headers files, or other derived files. The formatting ** of the code in this file is, therefore, important. See other comments ** in this file for details. If in doubt, do not deviate from existing *...
它与Parser关系紧密,根据语法分析树生成VDBE程序执行SQL语句的功能。 由诸多文件构成:trigger.c, update.c, insert.c, delete.c, select.c, where.c等文件。这些文件生成相应的VDBE程序指令,比如SELECT语句就由select.c生成。下面是一个读操作中打开表的代码的生成实现: /* Generate code that will open a ta...
view_name; SQLite DROP TRIGGER 语句DROP INDEX database_name.trigger_name; SQLite EXISTS 子句SELECT column1, column2...columnN FROM table_name WHERE column_name EXISTS (SELECT * FROM table_name ); SQLite EXPLAIN 语句EXPLAIN INSERT statement...; or EXPLAIN QUERY PLAN SELECT statement...; SQLi...
SQLite DROP TRIGGER 语句:DROP INDEX database_name.trigger_name;SQLite EXISTS 子句:SELECT column1, column2...columnN FROM table_name WHERE column_name EXISTS (SELECT * FROM table_name );SQLite EXPLAIN 语句:EXPLAIN INSERT statement...; or EXPLAIN QUERY PLAN SELECT statement...;SQLite...
不同于INSERT and DELETE触发器,UPDATE触发器可以定义在一个表的特定的字段上。The general form of this kind of trigger is as follows: CREATE TRIGGER name [BEFORE|AFTER] UPDATE OF column ON table action The following is a SQL script that shows an UPDATE trigger in action: ...
comment COMMIT TRANSACTION COPY CREATE INDEX CREATE TABLE CREATE TRIGGER CREATE VIEW DELETE DETACH DATABASE DROP INDEX DROP TABLE DROP TRIGGER DROP VIEW END TRANSACTION EXPLAIN expression INSERT ON CONFLICT clause PRAGMA REPLACE ROLLBACK TRANSACTION ...
SQLite CREATE TRIGGER 语句 CREATE TRIGGER database_name.trigger_name BEFORE INSERT ON table_name FOR EACH ROW BEGIN stmt1; stmt2; ... END; 复制 SQLite CREATE VIEW 语句 CREATE VIEW database_name.view_name AS SELECT statement...; 复制 SQLite CREATE VIRTUAL TABLE 语句 CREATE VIRTUAL TABLE...
-- 创建触发器 CREATE TRIGGER after_insert_user AFTER INSERT ON users BEGIN INSERT INTO user_logs(user_id, action, timestamp) VALUES (NEW.id, 'INSERT', CURRENT_TIMESTAMP); END; -- 删除触发器 DROP TRIGGER after_insert_user; 创建和管理分区表 分区表允许将表数据分割存储在不同的物理存储区域...
CREATE TRIGGER CREATE VIEW DELETE DETACH DATABASE DROP INDEX DROP TABLE DROP TRIGGER DROP VIEW END TRANSACTION EXPLAIN 表达式 INSERT ON CONFLICT子句 PRAGMA REINDEX REPLACE ROLLBACK TRANSACTION SELECT UPDATE VACUUM ALTER TABLE SQLite版本的的ALTER TABLE命令允许用户重命名或添加新的字段到已有表中,不能从表...
SQLite CREATE TRIGGER 语句 CREATE TRIGGER database_name.trigger_name BEFORE INSERT ON table_name FOR EACH ROW BEGIN stmt1; stmt2; ... END; SQLite CREATE VIEW 语句 CREATE VIEW database_name.view_name AS SELECT statement...; SQLite 创建虚拟表语句 CREATE...