sql server update query with inner join

Label:Using EF's own small functions need to encounter inner join and group by combination of use and anonymous type of processing, search a lot, basically can not meet their own needs, so summed up also realized on their own write out, has been prepared to view and partner query Reference (General statement query does

connection and the internal connection. This is often used in data analysis troubleshooting. You can also use database collection operations to achieve this function.Statement 11: for example, union join, the SQL environment that can be executed is not found.Select O. ID, O. order_number, O. customer_id, C. ID, C. NameFrom orders o union join customers C on C. I

somecolumn in (SELECT lookupcolumn from dbo. smallertable) Select Bigtable.id, somecolumn from BigTable INNER JOIN (SELECT DISTINCT lookupcolumn FROM dbo. Smallertable) as s = dbo. Bigtable.somecolumn Finally the query cost and the above is not the same, at this time the query performance cost is the same, I believ

times, physical read 0 times, read 0 times, LOB logic read 0 times, lob physical read 0 times, lob read 0 times.Table ' Verifyprocess '. Scan Count 9, logical read 3,136 times, physical read 0 times, read 0 times, LOB logic read 0 times, lob physical read 0 times, lob read 0 times. The performance of this example looks like the total time overhead difference is not obvious, because the number of connected tables is small, and if the number of tables connected is more, the entire execution plan

Original link: http://www.powerxing.com/sql-join/In general, the use/difference of four joins can be described as: The LEFT join returns all records from the table (shop), even if there are no matching rows in the right table (Sale_detail). Right outer join, returns all records in the right table, even if

Joins are divided into:INNER JOIN???????????????????????? [INNER JOIN]Outer JOIN???????? (left outer join, right outer join)???????? [Left Join/left outer joins, right

right table, regardless of whether the table on the left has matching data: Select S.name,m.mark from student s right join Mark M on S.id=m.studentid Iv. fully connected-full join: Using the format as above has been explained above Remove the data from the left and right two tables, whether or not they match: Select S.name,m.mark from student s full join Mark M

Label:SQL JOIN SQL Join is used to query data from these tables based on the relationship between the columns in two or more tables Sometimes in order to get the complete result, we need to get the result from two or more tables, we need to execute the Join. Tables in the da

The following is a 137-row SQL statement. If you understand this, I want to know about left join and inner join. (My personal opinion only) The following is a piece of code: Select num1, num2, num3, num4, num5, num6, num7, num8, num9, num10, area. areacode, area. areaname, num11 From(Select area_code areacode, area_nam

element in a to match the result of all elements in B, that is, the n*m combination. SELECT * from A cross JOIN B AA BB -------- -------- Item 1 Item 3 ^ Item 1 Item 4 +--- the first element in a, matching all elements in B Item 1 Item 5 | Item 1 Item 6 v Item 2 Item 3 ^ Item 2 Item 4 +--- a second element that matches all elements in B Item 2 Item 5 | Item 2 Item 6 v

Label:--Build Table Table1,table2:CREATE TABLE table1 (ID int,name varchar (10))CREATE TABLE table2 (ID int,score int)Insert INTO table1 Select 1,leeInsert INTO table1 Select 2,zhangInsert INTO table1 Select 4,wangInsert INTO table2 Select 1,90Insert INTO table2 Select 2,100Insert INTO table2 select 3,70such as table-------------------------------------------------Table1 | table2 |-------------------------------------------------ID Name |id Score |1 Lee | 90 |2 Zhang 100 |4 Wang |3 70 |---------