db2 right outer join

A (Id,name)Data: (1, Zhang San) (2, John Doe) (3, Harry)B (Id,name)Data: (1, student) (2, teacher) (4, principal)Left JOIN Connection results:Select a.*,b.* from A left join B on A.id=b.id;1 31 Students2 Li 42 teacher3 Harry NULL NULLRight link result:Select a.*,b.* from A right join B on a.id=b.id;1 31 Studen

is not based on who, it only shows records that match the criteria.--------------------------------------------Note:The left JOIN operation is used to combine records from the source table in any from clause. Use the left JOIN operation to create an outer join of the side. The left

Employees table: Department Table: Select E.last_name,e.department_id,d.department_name From Employees E LEFT OUTER JOIN Departments D On (e.department_id = d.department_id); Select E.last_name, D.department_name From Employees e, departments D where e.department_id = d.department_id (+) left outer join The r

Label:1. Inner JoinsUse comparison operators to match rows in two tables based on the values of the columns that are common to each table2. Outer Joins1) Left Join/left outer join the right table without matching, behavior null, left table row reserved 2)

Left (outer) Join: The table is the main, which contains all the rows of the left table, and the right table satisfies the recorded data listRight (outer) join: The table that is the main, contains all the rows of the right table,

The following is an example: ExampleTable Aid adate1 A12 A23 A3 Table B Bid bdate1 B12 B24 B4 Left join: Select * from a left join B on A. Aid = B. Bid First, retrieve all the data in Table A, and then add the data that matches table A and table B.In this case, the following information is taken: 1 A1 B12 A2 B23 A3 null characters Right

In MYSQL, you can use the internal and external key links to merge data in related tables for conditional filtering:First, create two new tables. The data is as follows:Student table data:Score table data:We can see that the score table corresponding to the record with stu_id 16048008 in the students table has no data;1. When the internal connection is performed, the system automatically ignores the data that cannot be matched in the two tables:-- Display all data connected in:SELECT * FROM stud

Brief introduction In the actual situation, for example in a university, there are many teachers, teachers have their own research direction and title. And, perhaps not every teacher has a graduate student, if a new teacher, may not have brought graduate students. So, if the leader asks to find out all the teachers with the number of graduate students (no graduate students with 0), then you need to use the left/right

SQL Getting Started Tutorial: SQL Right JOIN right-hand SQL Right JOIN keywordThe RIGHT join keyword returns all rows from the right

lists the full-time employee information assigned to a project: 　　 SELECT Samp_project.name,Samp_project. PROJ, Samp_staff.name, Samp_staff. JOBFrom Samp_project, Samp_staffWHERE Samp_staff.name = Samp_project.name 　　 Alternatively, you can specify the following connections: 　　 SELECT Samp_project.name,Samp_project. PROJ, Samp_staff.name, Samp_staff. JOBFrom Samp_project INNER JOIN Samp_staffOn samp_staff.name = Samp_project.name 　　 The result: 　　 　

SQL Left, Right Join, and other operators.1. query all the data in tableA and tableB and the data in tableA in tableB.Select * from tableA A left join tableB B on A. key = B. key2. query and exclude the data in tableB and the remaining data in tableA.Select * from tableA A left join tableB B on A. key = B. key where B.

SQL join example. (Left join, right join, full join, inner join, cross join, and Self join) the following table is assumed: One is the vot

77895 Carter Thomas 44678 SELECT column_name (s) from table_name1 Left JOIN on table_name1.column_name=table_name2.column_nameSQL join-Using JoinIn addition to the above method, we can also use keyword JOIN to get data from two tables.If we want to list everyone's orders, you can use the following SELECT statement:SEL

Inner left right join statement SQL code CREATE TABLE 'A' ('a1' VARCHAR (10) DEFAULT NULL, 'b1 'varchar (10) DEFAULT NULL, 'c1' VARCHAR (10) default null) ENGINE = innodb default charset = utf8 www.2cto.com create table 'B' ('a2 'VARCHAR (10) DEFAULT NULL, 'b2' VARCHAR (10) DEFAULT NULL) ENGINE = innodb default charset = utf8: The data in the table is as follows: SQL statement execution result image: SQL co

shown here. This shows that inner join is not based on who, it only shows records that match the criteria.--------------------------------------------Note:The left JOIN operation is used to combine records from the source table in any from clause. Use the left JOIN operation to create an outer

Recently, the company is recruiting people. My colleagues asked a few questions about database connection that I think the database can be applied ~ Now I want to write about their functions here. Assume that the following table is used: One is the voting master table, and the other is the voter information table ~ Record the IP address of the voter and the corresponding voting type. The left-right connection is actually the result of our joint qu

Label:Http://www.cnblogs.com/zhangqs008/archive/2010/07/02/2341196.html The outer joins mainly include left join, right connection and complete external connection . 1) left-side connection: either Outer join The result set of the left j