constant database

A constant, also known as a text value or scalar value, is a symbol that represents a specific data value. The constant format depends on the Data Type of the value it represents. String constant String constants are enclosed

Article turned from: http://www.cnblogs.com/daocaoren/archive/2011/07/14/2106278.html1. What is a const?A constant type is a type that uses the const description of a type modifier, and the value of a variable or object of a constant type cannot be

1. What is a const?A constant type is a type that uses the const description of a type modifier, and the value of a variable or object of a constant type cannot be updated. (Of course, we can rescue to update:)2. Why is const introduced? The initial

1. What is const? A common type is a type described by the Type modifier Const. The values of variables or objects of a common type cannot be updated. (Of course, we can steal the bar for updating :) 2. Why is const introduced? The initial purpose

Use Java annotations to generate js files for front-end calls of constant classes Annotation is equivalent to a flag. Adding an annotation in the program is equivalent to marking the program. If it is not added, it means there is no mark. Later, the

A namespace (mainly for automatic load classes)* Namespace (equivalent to a virtual directory), in order for the class to have a unified folder to manage (can automatically load ' class '), each file must have a namespace*TP How to make

35. RecordCreateOptionsEnum constantThe name, value, and description of the RecordCreateOptionsEnum constant are shown in the table F-35.Table F-35RecordCreateOptionsEnum constant name, value, and descriptionName value descriptionAdCreateCollectio819

How does the data read from the database correspond to defined constants? Consstant. php: define (town_9, Hengli); define (town_10, Qiaotou); define (town_11, Xie Gang); define (town_12, Dongkeng); define (town_13, Changping ); define (town_14, skip

Note 002PHP data object (PDO) predefined constant name description PDO: PARAM_BOOL (integer) indicates the Boolean data type. PDO: PARAM_NULL (integer) indicates the NULL data type in SQL. PDO: PARAM_INT (integer) indicates an integer in SQL. PDO:

MySQL database BASICS (2) (constraints and modifying data tables) (in constant update), mysql updating I. Constraints and modify data tables What is the role of a constraint? 1. constraints ensure data integrity and consistency; 2. constraints are