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50 common SQL statementsStudent (S #, Sname, Sage, Ssex) Student tableCourse (C #, Cname, T #) CurriculumSC (S #, C #, score) Orders tableTeacher (T #, Tname) Instructor tableProblem:1. query the student ID of all students whose score is higher than that of the "002" course;Select a. S # from (select s #, score from SC where C # = '001') a, (select s #, scoreFrom SC where C # = '002') BWhere a. score> B. sc

50 common SQL statements Student (S #, Sname, Sage, Ssex) Student tableCourse (C #, Cname, T #) CurriculumSC (S #, C #, score) Orders tableTeacher (T #, Tname) Instructor table Problem:1. query the student ID of all students whose score is higher than that of the "002" course;Select a. S # from (select s #, score from SC where C # = '001') a, (select s #, scoreFrom SC where C # = '002') BWhere a. score> B.

Tags: blog use problem div code HTML Management logTo manage the job training information, establish 3 tables:S (S#,SN,SD,SA) S#,sn,sd,sa respectively represents the student number, the student name, the unit, the Student Age C (C#,CN) C#,CN respectively represents the course number, the course name SC (s#,c#,g) S#,c#,g respectively represents the student number, the elective

();}2. Parameters of the array typeProgram codeSELECT * from T_blog where ID in#{item}Correspondence MapperProgram codePublic list3. Parameters of the Map typeProgram codeSELECT * from T_blog where title like "%" #{title} "%" and ID in#{item}The mapper should be such an interface:Program codePublic listthrough the above method, we can complete the general MyBatis dynamic SQL statement. The most common is if where foreach these, must focus on masterin

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course (-59) Good (-80) Excellent (-100) Select Subject, (selectcountfromwhere and as failed, ( Select Count from where between and and as benign, (selectcountfromwhere and as excellent from Group by subject 13. Mathematics: Zhang San (50 points), John Doe (90 points), Harry (90 points), Zhao Liu (76 points) Declare @s varchar (1000) Set @s='select@s =@s+', '+name+' ('+convert (varchar(), score) +' points 'fromwhere subject=' mathematics ' Set

statement queries the number of employees in the department, where the ID and name of the employee are from the employee table, people_num from the Department table:The other Connection statement format is using the join on syntax, which is equivalent to the following statement:SELECT id,name,people_numFROM employee JOIN departmentON employee.in_dpt = department.dpt_nameORDER BY id;The result is the same as the statement just now.Second, practice1, using the method of connection query, the numb

Tags: SQL statementsDevelopment Course do practice Student Guide 051 les01 pptOracle often connects two tables, called a third paradigm, such as something with an ID characterThe following is the command for the SQL statementSELECT * from departments; Department tableSELECT * FROM Employees; Employee tableSelect Employee_id,rowid,rownum from Employeeswhere employ

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Tags: str utf8mb4 greater than ADE where name group drop coreUse an SQL statement to find out the names of students with more than 80 points in each course, with the following data table structure: The table SQL is built as follows: SETForeign_key_checks=0; -- ---------------------------- --Table structure for grade -- ---------------------------- DROP TABLE IF

There is a student table with three columns in total. The first column is the student ID column, which stores the student ID of the Course Selection. You can repeat it to allow one student to select multiple courses. The second column is the course column, that is, the name of the course selected. The third column is the score column, that is, the score of the

An SQL statement is used to query the names of students whose scores are greater than 80 in each course. There are three tables: S, C, and SC S (Sno, Sname) C (Cno, Cname) SC (Sno, Cno, grade) -------------------------------------------------- problem: use an SQL statement to query the names of students whose scores are greater than 80 in each

('John Doe','Mathematics',' -'); - INSERT into' Grade 'VALUES('Harry','language','Bayi'); + INSERT into' Grade 'VALUES('Harry','Mathematics',' -'); A INSERT into' Grade 'VALUES('Harry','English',' -'); at SETForeign_key_checks=1;View CodeCheck the names of students who have more than 80 points for each course:1 Select distinct from where not inch (Selectdistinctfromwhere score);View CodeThere is also a simple notation:1 Select from Group by ha

In SQL Sever 2008, if you need to query the top 3 of each course, the implementation is as follows:Existing score table (result), column (Studentno, subjectno account number, Studentresult student score)Method One:SELECT distinct b.* Fromresult as RCross APPLY (SELECT TOP (3) *from Result WHERE r.subjectno= subjectno ORDER by Studentresult DESC) as BOrder by Subjectno, Studentresult descCross apply () use t

Label:Name Kecheng FenshuZhang San language 81Zhang San Mathematics 75John Doe Language 76John Doe Mathematics 90Harry Language 81Harry Mathematics 100Harry English 90 Method One: 　　ideas: If you can get a table, by the student's name, language scores, math scores, English scores of the table, the rest is in the where conditions to filter and can get the desired results. 　　specific measures: through the self-linking method, with "name" as the connection condition, since the connection three time

the cache are output to a file;Spool off means that the cache is closed and the file is saved on its own initiative; [Email protected] ~]$ Sqlplus/as SYSDBA Sql*plus:release 10.2.0.1.0-production on Wed June 18 13:52:25 2014 Copyright (c) 1982, 2005, Oracle. All rights reserved. Connected to:Oracle Database 10g Enterprise Edition Release 10.2.0.1.0-productionWith the partitioning, OLAP and Data Mining options [Email Protected]>spool/home/oracl

); insert INTO Employee (Id,name) Span class= "Hljs-keyword" >values (03, ' Rose '); You've noticed that some data needs to be enclosed in single quotes, such as the names of Tom, Jack, and Rose, because their data types are char type. In addition, Varchar,text,date,time,enum and other types of data also require single-quote decoration, while int,float,double and so on are not required.The first statement is a bit more than the second: (Id,name,phone) This parenthesis is the data to be added