sql left join with where clause

point, the removal is:1 A1 B12 A2 B23 A3 NULL characterThe same is trueRight join Refers to the first to remove all the data in the B table, and then add the data that matches theAt this point, the removal is:1 A1 B12 A2 B24 NULL character B4Left JOIN or left OUTER join.The result set of the left outer

= B.bid The results are as follows:AID Anum BID bname1 a20050111 1 20060324012 a20050112 2 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.---------

The following is an exampleTable A records the following:Aid anum1 a200501112 a200501123 a200501134 a200501145 a20050115 Table B records the following:Bid bname1 20060324012 20060324023 20060324034 20060324048 2006032408 The SQL statements for creating these two tables are as follows:Create TableAid int (1) auto_increment primary key,Anum char (20))Create Table B (Bid int (1) not null auto_increment primary key,Bname char (20)) INSERT INTOValues (1, '

[Test @ ora1] SQL> select * From A; No. Name ---- ---------- 1000 Zhang San 2000 Li Si 3000 Wang Wu [test @ ora1] SQL> select * from B; product NO. ---- ---------- 1000 TV set 2000 video recorder 4000 bicycle [test @ ora1] SQL> set null Null Value -- Here I define null as [null value] [test @ ora1] SQL> select. *, B. *

Here is an example analysis Table A records as follows: AID Anum 1 a20050111 2 a20050112 3 a20050113 4 a20050114 5 a20050115 Table B is recorded as follows: BID bname 1 2006032401 2 2006032402 3 2006032403 4 2006032404 8 2006032408 Create the two tables SQL statements as follows: CREATE TABLE A AID Int (1) auto_increment PRIMARY KEY, Anum Char (20) ) CREATE TABLE B ( BID Int (1) not NULL auto_increment PRIMARY KEY, Bname Char (20) ) INSERT into a V

SQL statement is as follows:Select * fromRight joing BOn a. Aid = B. Bid The result is as follows:Aid anum bid bname1 A11 1 B112 A22 2 B223 A33 3 B334 A44 4 b44Null null 8 b88(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

Tags: ar using SP data on EF BS SQL MySQLHere is an example analysisTable A records the following:AID Anum1 a200501112 a200501123 a200501134 a200501145 a20050115Table B records the following:BID bname1 20060324012 20060324023 20060324034 20060324048 2006032408Create these two table SQL statements as follows:CREATE TABLE AAID Int (1) auto_increment PRIMARY KEY,Anum Char (20))CREATE TABLE B (BID Int (1) not N

definition: Left join (left-hand join) returns a record that includes all records in the left table and the join fields in the right table Right join (right-click

Here is an example analysisTable A records the following:AID Anum1 a200501112 a200501123 a200501134 a200501145 a20050115Table B records the following:BID bname1 20060324012 20060324023 20060324034 20060324048 2006032408Create these two table SQL statements as follows:CREATE TABLE AAID Int (1) auto_increment PRIMARY KEY,Anum Char (20))CREATE TABLE B (BID Int (1) not NULL auto_increment PRIMARY KEY,Bname Char (20))INSERT into aVALUES (1, ' a20050111 '),

Here is an example analysisTable A records the following:AID Anum1 a200501112 a200501123 a200501134 a200501145 a20050115Table B records the following:BID bname1 20060324012 20060324023 20060324034 20060324048 2006032408Create these two table SQL statements as follows:CREATE TABLE AAID Int (1) auto_increment PRIMARY KEY,Anum Char (20))CREATE TABLE B (BID Int (1) not NULL auto_increment PRIMARY KEY,Bname Char (20))INSERT into aVALUES (1, ' a20050111 '),

Left join, join, right join difference, leftjoinLeft join returns records that include all records in the left table and join fields in the right table.Right

Label:Left join returns records that include all the records in the left table and the equivalent of the junction fields in the right tableRight join returns records that include all records in the right table and the junction fields in the left tableINNER JOIN (equivalent

Left join returns records that include all the records in the left table and the equivalent of the junction fields in the right tableRight join returns records that include all records in the right table and the junction fields in the left tableINNER

Tags: description database table selection No related detailed associated demo postFirst, let's look at some of the simplest examples. Example Table AAid Adate1 A12 A23 A3 TableB Bid Bdate1 B12 B24 B4Two tables A, B connected, to remove fields with the same IDSELECT * from a INNER join B on a.aid = B.bid This is only the matching data is taken out.At this point, the removal is:1 A1 B12 A2 B2Then the left

Mysql Left Join, Inner Join instance tutorialLeft Join and Inner Join are useful for understanding the principles and specific applications!I. Let's take a look at some of the simplest examples. Example TableAid adate1 a12 a23 a3 TableB Bid bdate1 b12 b24 b4Two tables a and

bname1 a20050111 1 20060324012 a20050112 2 20060324023 a20050113 3 20060324034 a20050114 4 2006032404Null 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 joinThe

tb_bo_valusr_new B on. usr_nbr = B. usr_nbr and. if_wlg = 'yes'; -- the result of running for 25 minutes has not been returned. In this example, the tb_bo_valusr_new table in Table B contains the full monthly number of the current month, and the monthly number is not repeated, table tmp_msy_bj_001 does not have repeated records. In this example, if you use where to specify the constraints of the non-join field of B after

SQL left join keyword The left join keyword returns all rows from the left table (table_name1), even if no matching row exists in the right table (table_name2. Left

row in the same two tables meets the join conditions. The inner join removes rows that do not match any row in the other table. Outer Join will return fromAll rows of at least one table or view mentioned in the clause, as long as these rows comply with any where or havingSearch criteria. Searches all rows in the

An Introduction to left join, right join and full join in oracle is from oracle ocp9i document: outer join syntax: 1) you use an outer join to also see rows that do not meet the join co