PTA deletes the grade record score of girls who take the C language course 10

SQL practice collection

This topic requires writing a DELETE statement to delete the course selection records of girls who take the 'C language' course.

Table Structure:

Please write the SQL statement that defines the table structure here. For example:

CREATE TABLE `stu` (
  `sno` char(4) NOT NULL, 
  `sname` char(8) NOT NULL,
  `sex` tinyint(1) DEFAULT NULL,  --0为女生,1为男生。
  `mno` char(2) DEFAULT NULL,
  `birdate` datetime DEFAULT NULL,
  `memo` text,
  PRIMARY KEY (`sno`)
);
CREATE TABLE `cou` (
  `cno` char(4) NOT NULL,
  `cname` varchar(30) NOT NULL,
  `credit` smallint(6) DEFAULT NULL,
  `ptime` char(5) DEFAULT NULL,
  `teacher` char(10) DEFAULT NULL,
  PRIMARY KEY (`cno`)
)
CREATE TABLE `sc` (
  `sno` char(4) NOT NULL,
  `cno` char(4) NOT NULL,
  `grade` decimal(6,1) DEFAULT NULL,
  PRIMARY KEY (`sno`,`cno`),
  CONSTRAINT `fk_sc_cno` FOREIGN KEY (`cno`) REFERENCES `cou` (`cno`),
  CONSTRAINT `fk_sc_sno` FOREIGN KEY (`sno`) REFERENCES `stu` (`sno`)
)

table sample

Please give a table sample corresponding to the above table structure here. For example

Stu table:

cou table:

sc table:

Sample output:

After deleting the record, the sc table is as follows:

Code length limit 16 KB

Time limit 400 ms

DatabaseMySQL

The result output requires a strict comparison of the order and data

delete from sc
where sno in(
    select sno
    from stu
    where sex = 0
)and cno in(
    select cno
    from cou
    where cname = 'C语言'
)

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Origin blog.csdn.net/weixin_70206677/article/details/129360384