insert primary key

Key differs from primary keyKey is usually the index synonym. If the keyword attribute primary key is given in the column definition, then primary key can also be specified as key only. The purpose of this is to be compatible with other database

Primary Key and foreign key in the database, primary key of the database 1. What are primary keys and Foreign keys: A record in a relational database has several attributes. If one of the attribute groups (note that it is a group) uniquely

The definition of a primary key: A collection of columns or columns that is used to uniquely identify a row in a table. Only one primary key is allowed on a table.When we specify a primary key in the database, it is defined by a PRIMARY key

As an important mechanism for periodically cleaning up invalid data, primary key failures exist in most caching systems, and Redis is no exception. Of the many commands provided by Redis, EXPIRE, Expireat, Pexpire, Pexpireat, and Setex and Psetex

For example, there are three fields: Table person, person, id (mysql database, primary key, non-auto-increment), and name and pswd. In the case of auto-increment, we usually process insertintoperson (name, pswd) values (# {name}, # {pswd}) in this

This article is referenced from:http://blog.csdn.net/bingqingsuimeng/article/details/51595560First, what is the primary key, foreign key:There are several attributes in a record in a relational database, which can be a primary key if one of the

First, what is the primary key, foreign key:There are several attributes in a record in a relational database, which can be a primary key if one of the attribute groups (note is a group) uniquely identifies a record:Student Table (School number,

First, what is primary key, foreign key:A record in a relational database has several properties, and if one of the attribute groups (note the group) uniquely identifies a record, the attribute group can be a primary key such as: Student form

In our database design, the primary key of the database table is unavoidable. Many may not think deeply about it. The design of the primary key has a great impact on the design of the entire database, therefore, we have to pay attention to it.

Conceptual differences:Primary key: Refers to a column where the field is unique and is not a null value.Primary key index: refers to the primary key, the primary key does not have a clear concept definition, the primary key is both a constraint, an