Multiple If Statement

SQL used to manipulate the database is generally divided into two kinds, one is the query, which is what we call the SELECT statement, the other is to update the statement, also known as data manipulation statements. The implication is to modify the data. There are 3 statements in the standard SQL, which are INSERT, UPDATE, and DELETE. There is another REPLACE statement in MySQL, so this article uses MySQL as a background to discuss how to make updates in SQL. First, INSERT and REPLACE I ...

The complete collection of SQL statement operations deserves to be permanently stored the following statements are part of the MSSQL statement and are not available in Access. SQL classification: ddl-data Definition language (create,alter,drop,declare) dml-Data Manipulation Language (Select,delete,update,insert) dcl-Data Control Language (Grant,revoke, Commit,rollback first, briefly introduce the basic statement: 1, Description: Create number ...

loop when you write code, you often need to have the same code block run many times. You can use loop statements in your code to accomplish this task. In PHP, we can use the following loop statement: While as long as the specified condition is set, the circular execution code block Do...while executes the code block first, and then repeats the loop for the execution of the code block specified when the specified condition is set. foreach Loops The block of code based on each element in the array as long as it refers to ...

1, use the index to traverse the table faster. The index created by default is a non-clustered index, but sometimes it is not optimal. Under non-clustered indexes, the data is physically stored on the data page. Reasonable index design should be based on the analysis and prediction of various inquiries. In general: a. There are a large number of duplicate values, and often range query (>, <,> =, <=) and order by, group by occurred columns, consider the establishment of cluster index; Column, and each column contains duplicate values ​​can be ...

1, use the index to traverse the table faster. The index created by default is a non-clustered index, but sometimes it is not optimal. Under non-clustered indexes, the data is physically stored on the data page. Reasonable index design should be based on the analysis and prediction of various inquiries. In general: a. A large number of duplicate values, and often range query (>, <,> =, <=) and order by, group by occurred column, consider the establishment of cluster index; b. Column, ...

Beijing News (Reporter Liu Xiaowei Wei) In response to media coverage supplier Sunny Cheung through the United States and excellent products, Jingdong, No. 1 stores and other e-commerce platform for alleged fraud, July 28 afternoon, the United States gifted Product release statement responded that it has closed "Cheung Peng Peng Yee," the store, Jingdong also made a statement that it will close the shop. Both sides said they will provide unconditional return service. Yesterday, Tencent reported that "unannounced visits to the chain of e-commerce fake: the United States and other intellectual property fake sales," a text that was unveiled by the unofficial interview revealed that there is a supplier Cheung Peng Heng through multiple e-commerce platform to sell fake cheap luxury goods, these electricity Business platform including poly-US high-quality goods ...

Method 1 delete yourtable where [id] not in (select max ([id]) from yourtable group by (name + value) b on a.id = b.id where b.id ...

This article introduces a MySQL batch intercept the last separated part of the SQL statement to another field to have a friend in need of reference. --field images saved data is: A.jpg;b.jpg;c.jpg to the images of the last picture c.jpg assignment to Images_default execution of the SQL statement is the code as follows UPDATE product SET ' Image_ Default ' = REVERSE ...

March 19, often in Dangdang to buy books Changchun citizen Mr. Liu received the urgent notice from Dangdang. The notice said, Dangdang individual account of the appearance of gift cards stolen by criminals, in order to user accounts and funds security, Dangdang will be March 19 to March 21 to freeze the user account of the gift card and the balance, and please users in this period to the password to change the login. 　　For a time, Dangdang into the "account stolen door", and the security of the network account is placed in front of people. Multiple user accounts stolen Dangdang attitude before and after the "big turn" said the account was ...

Absrtact: Xiamen 35 Interconnection Technology Co., Ltd. (hereinafter referred to as 35 interconnection) involved in a big storm. Recently, some media reported that, because the company was alleged to have forged official documents registered network domain name, by the Internet domain name Investors Zheng Minjie Prosecution, the public Xiamen 35 Interconnection Technology Co., Ltd. (hereinafter referred to as 35 interconnection) involved in a big storm. Recently, some media reported that, because the company was alleged to counterfeit documents registered network domain name, by the Internet domain name Investors Zheng Minjie prosecution, the company also suspended the announcement of the relevant clarification, and yesterday (April 6) from the recovery card ...