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分类: LINUX
2015-11-28 14:13:17
SQL is followed by unique set of rules and guidelines called Syntax. This tutorial gives you a quick start with SQL by listing all the basic SQL Syntax:
All the SQL statements start with any of the keywords like SELECT, INSERT, UPDATE, DELETE, ALTER, DROP, CREATE, USE, SHOW and all the statements end with a semicolon (;).
Important point to be noted is that SQL is case insensitive, which means SELECT and select have same meaning in SQL statements, but MySQL makes difference in table names. So if you are working with MySQL, then you need to give table names as they exist in the database.
All the examples given in this tutorial have been tested with MySQL server.
SELECT column1, column2....columnN FROM table_name;
SELECT DISTINCT column1, column2....columnN FROM table_name;
SELECT column1, column2....columnN FROM table_name WHERE CONDITION;
SELECT column1, column2....columnN FROM table_name WHERE CONDITION-1 {AND|OR} CONDITION-2;
SELECT column1, column2....columnN FROM table_name WHERE column_name IN (val-1, val-2,...val-N);
SELECT column1, column2....columnN FROM table_name WHERE column_name BETWEEN val-1 AND val-2;
SELECT column1, column2....columnN FROM table_name WHERE column_name LIKE { PATTERN };
SELECT column1, column2....columnN FROM table_name WHERE CONDITION ORDER BY column_name {ASC|DESC};
SELECT SUM(column_name) FROM table_name WHERE CONDITION GROUP BY column_name;
SELECT COUNT(column_name) FROM table_name WHERE CONDITION;
SELECT SUM(column_name) FROM table_name WHERE CONDITION GROUP BY column_name HAVING (arithematic function condition);
CREATE TABLE table_name( column1 datatype, column2 datatype, column3 datatype, ..... columnN datatype, PRIMARY KEY( one or more columns ) );
DROP TABLE table_name;
CREATE UNIQUE INDEX index_name ON table_name ( column1, column2,...columnN);
ALTER TABLE table_name DROP INDEX index_name;
DESC table_name;
TRUNCATE TABLE table_name;
ALTER TABLE table_name {ADD|DROP|MODIFY} column_name {data_ype};
ALTER TABLE table_name RENAME TO new_table_name;
INSERT INTO table_name( column1, column2....columnN) VALUES ( value1, value2....valueN);
UPDATE table_name SET column1 = value1, column2 = value2....columnN=valueN [ WHERE CONDITION ];
DELETE FROM table_name WHERE {CONDITION};
CREATE DATABASE database_name;
DROP DATABASE database_name;
USE database_name;
COMMIT;
ROLLBACK;