首先需要建立兩張有關(guān)聯(lián)的表，隨便建了個課表和學(xué)生信息桑嘶。
設(shè)置一個外鍵使兩張表形成關(guān)聯(lián)
下面是簡單SQL語句的運用
查詢
SELECT id,studentname FROM students;
篩選出不重復(fù)的課程
SELECT DISTINCT classID FROM students;
按某一順序排列
SELECT studentname,age,studentID
FROM students
ORDER BY studentID;
在表中插入數(shù)據(jù)
INSERT INTO curriculum
VALUES (1006,"體育","彭老師");
搜索列中的指定模式
SELECT studentID
FROM students
WHERE studentID LIKE '%4';
搜索兩表中相匹配的列
SELECT classID
FROM students
INNER JOIN curriculum
ON students.classID=curriculum.id
返回左表中所有的行 即使右表中沒有匹配 沒有匹配即顯示為Null
SELECT studentname,classID
FROM students
LEFT JOIN curriculum
ON students.classID=curriculum.id
刪除表中某數(shù)據(jù)
DELETE FROM students
WHERE id=7;
修改表中數(shù)據(jù)
UPDATE curriculum
SET classname='思修',teacher='周老師'
WHERE id='1002';
