SQL 快速参考

常用的SQL 语句记录一下：

• AND / OR：SELECT column_name(s) FROM table_name WHERE condition AND|OR condition
• ALTER TABLE (add column)：ALTER TABLE table_name ADD column_name datatype
• ALTER TABLE (drop column)：ALTER TABLE table_name DROP COLUMN column_name
• AS (alias for column)：SELECT column_name AS column_alias FROM table_name
• AS (alias for table)：SELECT column_name FROM table_name AS table_alias
• BETWEEN：SELECT column_name(s) FROM table_name WHERE column_name BETWEEN value1 AND value2
• CREATE DATABASE：CREATE DATABASE database_name
• CREATE INDEX：CREATE INDEX index_name ON table_name (column_name)
  +CREATE TABLE：CREATE TABLE table_name (column_name1 data_type,
  column_name2 data_type,.......)
• CREATE UNIQUE INDEX：CREATE UNIQUE INDEX index_name ON table_name (column_name)
• CREATE VIEW：CREATE VIEW view_name AS SELECT column_name(s) FROM table_name WHERE condition
• DELETE FROM：DELETE FROM table_name (Note: Deletes the entire table!!) or DELETE FROM table_name WHERE condition
• DROP DATABASE：DROP DATABASE database_name
• DROP INDEX：DROP INDEX table_name.index_name
• DROP TABLE：DROP TABLE table_name
• GROUP BY：SELECT column_name1,SUM(column_name2) FROM table_name GROUP BY column_name1
• HAVING：SELECT column_name1,SUM(column_name2) FROM table_name GROUP BY column_name1 HAVING SUM(column_name2) condition value
• IN：SELECT column_name(s) FROM table_name WHERE column_name IN (value1,value2,..) INSERT INTO INSERT INTO table_name VALUES (value1, value2,....) or INSERT INTO table_name (column_name1, column_name2,...) VALUES (value1, value2,....)
• LIKE：SELECT column_name(s) FROM table_name WHERE column_name LIKE pattern
• ORDER BY：SELECT column_name(s) FROM table_name ORDER BY column_name [ASC|DESC]
• SELECT：SELECT column_name(s) FROM table_name
• SELECT *：SELECT * FROM table_name
• SELECT DISTINCT：SELECT DISTINCT column_name(s) FROM table_name
• SELECT INTO：(used to create backup copies of tables) SELECT * INTO new_table_name FROM original_table_name or SELECT column_name(s) INTO new_table_name FROM original_table_name
• TRUNCATE TABLE：(deletes only the data inside the table) TRUNCATE TABLE table_name
• UPDATE：UPDATE table_name SET column_name=new_value [, column_name=new_value] WHERE column_name=some_value
• WHERE：SELECT column_name(s) FROM table_name WHERE condition
  ---- 摘自 W3School ----