Home Database Mysql Tutorial Summary of definition and usage of control flow functions

Summary of definition and usage of control flow functions

Jun 14, 2017 am 09:41 AM

Grammar: CASE value WHEN [compare-value] THEN result [WHEN [compare-value] THEN result ...] [ELSE result] END CASE WHEN [condition] THEN result [WHEN [condition] THEN result ... ] [ELSE result] END In the return result of the first solution, value=compare-value. The return result of the second scenario is the true result of the first scenario. If there is no matching result value, the return result is the result after ELSE. If there is no ELSE part, the return value is NULL. mysql> SELECT CASE 1

1. MySQL Basic Tutorial 6 - Function Control Flow Function

Summary of definition and usage of control flow functions

##Introduction: Syntax: CASE value WHEN[compare-value]THEN result [WHEN[compare-value]THEN result ...][ELSE result]ENDCASEWHEN[condition]THEN result [WHEN[c ...

2. Detailed introduction to basic learning of Linux shell scripts (5)

Summary of definition and usage of control flow functions

Introduction: The basics of Linux shell scripts have been divided into several parts. The content of the control process will be finished here. This is the last part about the here document. The example here is a bit complicated. Let's take our time to analyze this complex Linux shell script.

3. Detailed introduction to basic learning of Linux shell scripts (4)

Summary of definition and usage of control flow functions

Introduction: In the previous article on basic learning of Linux shell scripts, we talked about the if, select, and case control processes in Linux shell scripts. Here we will introduce the loop and quotation marks of the control process in Linux shell scripts. The control process is Some of the content is quite extensive, and some of the content is about the here document.

4. Detailed introduction to basic learning of Linux shell scripts (2)

Summary of definition and usage of control flow functions

Introduction: The previous lecture of the basic Linux shell scripting course introduced the beginning, comments, variables and environment variables of the basic grammar. Here we will introduce the first part of the shell command and control process. In the shell script, you can Use three types of commands, and leave the control process in the next lecture.

5. Detailed explanation of Boolean variables of PHP data types

Summary of definition and usage of control flow functions

##Introduction: Summary: Boolean types are mostly used to control processes. When comparing two objects, you can use "==" to determine whether it is true. In addition, when using Boolean variables for process control, you can use them directly without comparing with the true keyword, as shown in Program 2-4. Show. ...

6.

mysql control process function

Summary of definition and usage of control flow functions##Introduction: CASE value WHEN [compare-value] THEN result [WHEN [compare-value] THEN result ...] [ELSE result] END CASE WHEN [condition] THEN result [WHEN [condition] THEN result .. .] [ELSE result] END

7.

How to flexibly use if examples in MySQL statements

Introduction : The following article mainly describes the actual operation steps of how to use if examples in MySQL statements. We first introduce the actual operations of how to use if examples in MySQL statements in the form of relevant codes. The following is a description of the specific operation content of the article. Hope you will gain something. *,if(sva = 1,male,female)asssvafromtanamewheresva 12.2. Control flow function

8. Small collection of Petlai project experience (5)___System process design

Summary of definition and usage of control flow functions

Introduction: There is a process design issue in the Petola project design. Although both .NET and Java have workflows, considering the small size of this project, here I will simply borrow some workflow ideas and design I created several tables and then controlled the process through code. Let's take the physical process in the maintenance appraisal form business process as an example to talk about the specific process design. There is a physical maintenance certificate

9. MySQL control process function

Introduction: Welcome to the Linux Community Forum, Interact and communicate with 2 million technical personnel>>Enter CASE value WHEN [compare-value] THEN result [WHEN [compare-value] THEN result ...] [ELSE result] END CASE WHEN [condition] THEN result [WHEN [ condition] THEN result ...] [ELSE result] E

10. What are the basics of a programming language?

Introduction: For example 1. A hello world including the environment 2. Data type 3. Function 4. Operator 5. Control flow. . . Please add that I have sorted out the basic knowledge of php python java c. Thank you

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