mysql sum if

Mysql uses sumif to perform row-to-column conversion (the row table data is as follows). First, we should consider how to create a column structure [SQL] viewplaincopySELECTNAMEAS name, IF (type language, score, 0) ASyuwen, IF (type mathematics,

Chapter 23. Precision mathTable of contents 23.1. Types of numeric values23.2. decimal data type changes23.3. Expression handling23.4. Rounding Behavior23.5. Precision math examplesMySQL 5 introduces precision math, that is, numeric value handling

Concrete Example 1. PHP Server ComponentsFor beginners, it is recommended to use the integrated server component, which already includes PHP, Apache, Mysql and other services, eliminating the time spent by developers in the tedious configuration

In mysql, there are two functions: count () and sum (). Many of them are confused. From an English perspective, we can find that count is the number of statistics, sum is the sum of values and can only be numeric. In mysql, there are two functions:

How PHP calculates the sum of the data in a field of MySQL Reply content: How PHP calculates the sum of the data in a field of MySQL phpUse foreach traversal to accumulate the fields you want to sum mysqlcan be used SUM SELECT

Original table:Id fenlei time1 Category 1 201303162 Category 2 201303163 Category 3 201303174 category 2 201303175 Category 3 20130318 You need to check the table above and insert the result to the new table.New table structure: Id fenlei_1 fenlei_2

This article mainly introduces the method of calculating the sum and product of the values in the PHP array, and analyzes the function and use of the array_sum and array_product functions in detail in the case form, and a friend can refer to the

Mysql and Oracle use the rollup function to complete row and column statistics ??? Yesterday, I suddenly saw in a blog that Mysql also had the rollup function. The original blog post used rollup for row and column statistics. The original blog post

Sum optimization and indexing in mysql // Create table if not exists 'radacct '('radacctid' bigint (21) not null AUTO_INCREMENT, 'username' varchar (64) not null default '', 'acctsessiontime' int (12) default null, 'acctinputoctets 'bigint (12)

Recently in the company to do projects, involving the development of statistical reports related to the task, due to the relatively large amount of data, the query before writing query 500,000 data about 10 seconds to look like, later through the