SQL 快速参考
来自 W3School 的 SQL 快速参考。可以打印它，以备日常使用。
SQL 语句 ¶
| 语句 | 语法 |
|---|---|
| AND / OR | SELECT column_name(s) FROM table_name WHERE condition AND/OR condition |
| ALTER TABLE (add column) | ALTER TABLE table_nameADD column_name datatype |
| ALTER TABLE (drop column) | ALTER TABLE table_nameDROP COLUMN column_name |
| AS (alias for column) | SELECT column_name AS column_aliasFROM table_name |
| AS (alias for table) | SELECT column_nameFROM table_name AS table_alias |
| BETWEEN | SELECT column_name(s)FROM table_nameWHERE column_nameBETWEEN value1 AND value2 |
| CREATE DATABASE | CREATE DATABASE database_name |
| CREATE INDEX | CREATE INDEX index_nameON 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_nameON table_name (column_name) |
| CREATE VIEW | CREATE VIEW view_name ASSELECT column_name(s)FROM table_nameWHERE condition |
| DELETE FROM | DELETE FROM table_name(Note: Deletes the entire table!!)orDELETE FROM table_nameWHERE 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_nameGROUP BY column_name1 |
| HAVING | SELECT column_name1,SUM(column_name2)FROM table_nameGROUP BY column_name1HAVING SUM(column_name2) condition value |
| IN | SELECT column_name(s)FROM table_nameWHERE column_nameIN (value1,value2,..) |
| INSERT INTO | INSERT INTO table_nameVALUES (value1, value2,….)orINSERT INTO table_name(column_name1, column_name2,…)VALUES (value1, value2,….) |
| LIKE | SELECT column_name(s)FROM table_nameWHERE column_nameLIKE pattern |
| ORDER BY | SELECT column_name(s)FROM table_nameORDER BY column_name [ASC |
| 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_nameFROM original_table_nameorSELECT column_name(s)INTO new_table_nameFROM original_table_name |
| TRUNCATE TABLE(deletes only the data inside the table) | TRUNCATE TABLE table_nameUPDATE UPDATE table_nameSET column_name=new_value[, column_name=new_value]WHERE column_name=some_value |
| WHERE | SELECT column_name(s)FROM table_nameWHERE condition |