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3.SQL常用命令一览表

huoxiaoqiang • • SQL教程 • 阅读 488

1.数据库(DATABASE)

语句语法
CREATE DATABASECREATE DATABASE database_name
DROP DATABASEDROP DATABASE database_name

2.表(TABLE)

语句语法
CREATE TABLECREATE TABLE table_name
(
column_name1 data_type,
column_name2 data_type,
…….
)
DROP TABLEDROP TABLE table_name
TRUNCATE TABLE
(deletes only the data inside the table)		TRUNCATE TABLE table_name
AS (alias for table)SELECT column_name
FROM table_name  AS table_alias

3.行(RECORD)

语句语法
SELECTSELECT column_name(s)
FROM table_name
SELECT *SELECT *
FROM table_name
SELECT DISTINCTSELECT DISTINCT column_name(s)
FROM table_name
WHERESELECT column_name(s)
FROM table_name
WHERE condition
SELECT INTO
(used to create backup copies of tables)		SELECT *
INTO new_table_name
FROM original_table_nameor
SELECT column_name(s)
INTO new_table_name
FROM original_table_name
INSERT INTOINSERT INTO table_name
VALUES (value1, value2,….)or
INSERT INTO table_name
(column_name1, column_name2,…)
VALUES (value1, value2,….)
UPDATEUPDATE table_name
SET column_name=new_value
[, column_name=new_value]
WHERE column_name=some_value
DELETE FROMDELETE FROM table_name
(Note: Deletes the entire table!!)or
DELETE FROM table_name
WHERE condition
AND / ORSELECT column_name(s)
FROM table_name
WHERE condition
AND|OR condition
ORDER BYSELECT column_name(s)
FROM table_name
ORDER BY column_name [ASC|DESC]
LIKESELECT column_name(s)
FROM table_name
WHERE column_name
LIKE pattern
INSELECT column_name(s)
FROM table_name
WHERE column_name
IN (value1,value2,..)
BETWEENSELECT column_name(s)
FROM table_name
WHERE column_name
BETWEEN value1 AND value2
GROUP BYSELECT column_name1,SUM(column_name2)
FROM table_name
GROUP BY column_name1

4.列(COLUMN)

语句语法
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

5.索引(INDEX)

语句语法
CREATE INDEXCREATE INDEX index_name
ON table_name (column_name)
CREATE UNIQUE INDEXCREATE UNIQUE INDEX index_name
ON table_name (column_name)
DROP INDEXDROP INDEX table_name.index_name

6.备注

SQL 语句对大小写不敏感。SELECT 等效于 select。

某些数据库会要求末尾加上;号，正常不需要加，如果加的话，可以一行运行多条命令。

原创文章，作者：huoxiaoqiang，如若转载，请注明出处：https://www.huoxiaoqiang.com/basic/sql/1899.html

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