sql left join with where clause

publisher equals book. publisher into publisherbooks select new {publisher = publisher. name, books = publisherbooks}; gridviewgroupjoin. databind (); AboveCodeIs the so-called "group connection ". It groups the books of each publishing house into publisherbooks and binds them together. This code is consistent with the running result of the following code. VaR x = from book in sampledata. Books Group book by book. Publisher into bookpublishers select new {publisher = bookpublishers. Key. Na

2006032402 3 a20050113 3 2006032403 4 a20050114 4 2006032404 Null null 8 2006032408 (The number of affected rows is 5) Result description: After careful observation, we will find that the result of left join is exactly the opposite. This time, it is based on the right table (B) and is filled with null when table A is insufficient. 3. Inner join The

not equivalent.INNER JOINIs used withONClause,CROSS JOINIs used otherwise.Mentioned in the manualIn standard SQL, cross join (Cartesian product) is different from inner join. However, in MySQL, the two are the same, that is, [cross | inner] Join, which can be replaced by each other, you can only use

Equivalent to the following SQL sentence: The code is as follows Copy Code SELECT *From A,bWHERE A.aid = B.bid The results are as follows:AID Anum BID bname1 a20050111 1 20060324012 a20050112 2 20060324023 a20050113 3 20060324034 a20050114 4 2006032404 Results show:Obviously, only the record of A.aid = B.bid is shown here. This shows that inner join is not

Code is as follows: Copy code SELECT * FROMInner join BON a. aID = B. bID Equivalent to the following SQL statement: The Code is as follows: Copy code SELECT *FROM a, BWHERE a. aID = B. bID The result is as follows:AID aNum bID bName1 a20050111 1 20060324012 a20050112 2 20060324023 a20050113 3 20060324034 a20050114 4 2006032404 Result description:Obviousl

In the following post, innerjoin = where = join Http://baike.360.cn/4241488/12057813.html Http://z.baidu.com/question/46996912.html? SI = 1 The connection statement used in the WHERE clause is called a recessive connection in the database language. Inner join ...... The connection generated by the on clause is calle

right connections, if the two sides can not match the conditions, then do not take out. 7.MySQL does not support external connections , and, accordingly, MySQL can use Union (union query) to isolate the left and right connections. 　　　The union query filters for duplicate rows, and union all does not filter for duplicate rows . 　　　union query, the number of SQL columns between the Union must be equal, the

|-------------------------------------------------idname|idscore|1lee|190|2zhang|2100|4wang|370|-------------------------------------------------The following are performed in Query AnalyzerOne, outer connection1. Concept: Includes a LEFT outer join, a right outer join, or a full outer join2. Left-side connection: oute

Equivalent to the following SQL sentence:SELECT *From A,bWHERE A.aid = B.bid The results are as follows:AID Anum BID bname1 a20050111 1 20060324012 a20050112 2 20060324023 a20050113 3 20060324034 a20050114 4 2006032404 Results show:Obviously, only the record of A.aid = B.bid is shown here. This shows that inner join is not based on who, it only shows the records that match the criteria.The

Tags: hibernate hql inner join left right Category: SQL Original address: Http://m33707.iteye.com/blog/829725Select from [Outer] The join on the left join returns all rows in "left_table" a

Data Table connection (left join, right join, inner join, Cartesian) -- Query analyzer execution:-- Create Table Table1, Table2:Create Table Table1 (ID int, name varchar (10 ))Create Table Table2 (ID int, score INT)Insert into Table1 select 1, 'lil'Insert into Table1 select 2, 'zhang'Insert into Table1 select

Inner join There are two tables A and B. The structure of Table A is as follows: Aid: int; identifies the seed, primary key, and auto-increment ID Aname: varchar The data, that is, the records from select * From A, are shown in 1: Figure 1: data in Table Table B has the following structure: Bid: int; identifies the seed, primary key, and auto-increment ID Bnameid: int Data, that is, the records from select * from B, are sh

20060324023 a20050113 3 20060324034 a20050114 4 2006032404NULL NULL 8 2006032408(The number of rows affected is 5 rows) Results show:With a closer look, you will find that the result of the left join is just the opposite, this time based on the right table (B), where a table is deficient with null padding. 3.inner JoinThe SQL statement is as follows:SELECT * f

LEFT outer join, a right outer join, or a full outer join2. Left-side connection: outer JOIN(1) The result set of the left outer join includes all rows of the

: SELECT * from a LEFT join B on a.aid = B.bid First Remove all the data in the a table, and then add the data that matches a A, then take out is: 1 A1 B1 2 A2 B2 3 A3 null character Similarly, right join refers to the first to remove all the data from table B, and then add the data that matches a a, and then take out the following: 1 A1 B1 2 A2 B2 4 null charac

Take a look at the results of the left join and the right join with the Inner join and the full join to manipulate the table. Create a new two table in the database and insert the data you want to test. New table:[SQL