• SQL 快速参考


    SQL 快速参考


    SQL 语句语法
    AND / OR SELECT column_name(s)
    FROM table_name
    WHERE condition
    AND|OR condition
    ALTER TABLE ALTER TABLE table_name 
    ADD column_name datatype

    or

    ALTER TABLE table_name 
    DROP COLUMN column_name

    AS (alias) SELECT column_name AS column_alias
    FROM table_name

    or

    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 TABLE CREATE TABLE table_name
    (
    column_name1 data_type,
    column_name2 data_type,
    column_name2 data_type,
    ...
    )
    CREATE INDEX CREATE INDEX index_name
    ON table_name (column_name)

    or

    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 DELETE FROM table_name
    WHERE some_column=some_value

    or

    DELETE FROM table_name 
    (Note: Deletes the entire table!!)

    DELETE * FROM table_name 
    (Note: Deletes the entire table!!)

    DROP DATABASE DROP DATABASE database_name
    DROP INDEX DROP INDEX table_name.index_name (SQL Server)
    DROP INDEX index_name ON table_name (MS Access)
    DROP INDEX index_name (DB2/Oracle)
    ALTER TABLE table_name
    DROP INDEX index_name (MySQL)
    DROP TABLE DROP TABLE table_name
    GROUP BY SELECT column_name, aggregate_function(column_name)
    FROM table_name
    WHERE column_name operator value
    GROUP BY column_name
    HAVING SELECT column_name, aggregate_function(column_name)
    FROM table_name
    WHERE column_name operator value
    GROUP BY column_name
    HAVING aggregate_function(column_name) operator value
    IN SELECT column_name(s)
    FROM table_name
    WHERE column_name
    IN (value1,value2,..)
    INSERT INTO INSERT INTO table_name
    VALUES (value1, value2, value3,....)

    or

    INSERT INTO table_name
    (column1, column2, column3,...)
    VALUES (value1, value2, value3,....)

    INNER JOIN SELECT column_name(s)
    FROM table_name1
    INNER JOIN table_name2 
    ON table_name1.column_name=table_name2.column_name
    LEFT JOIN SELECT column_name(s)
    FROM table_name1
    LEFT JOIN table_name2 
    ON table_name1.column_name=table_name2.column_name
    RIGHT JOIN SELECT column_name(s)
    FROM table_name1
    RIGHT JOIN table_name2 
    ON table_name1.column_name=table_name2.column_name
    FULL JOIN SELECT column_name(s)
    FROM table_name1
    FULL JOIN table_name2 
    ON table_name1.column_name=table_name2.column_name
    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 SELECT *
    INTO new_table_name [IN externaldatabase]
    FROM old_table_name

    or

    SELECT column_name(s)
    INTO new_table_name [IN externaldatabase]
    FROM old_table_name

    SELECT TOP SELECT TOP number|percent column_name(s)
    FROM table_name
    TRUNCATE TABLE TRUNCATE TABLE table_name
    UNION SELECT column_name(s) FROM table_name1
    UNION
    SELECT column_name(s) FROM table_name2
    UNION ALL SELECT column_name(s) FROM table_name1
    UNION ALL
    SELECT column_name(s) FROM table_name2
    UPDATE UPDATE table_name
    SET column1=value, column2=value,...
    WHERE some_column=some_value
    WHERE SELECT column_name(s)
    FROM table_name
    WHERE column_name operator value
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  • 原文地址:https://www.cnblogs.com/cisum/p/8066263.html
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