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 ----
