Structured Query Language (SQL), referred to as SQL, is a special-purpose programming language. It is a database query and programming language used to access data and query, update and manage relational database systems; at the same time It is also the extension of the database script file. Next I will talk to you about learning SQL.
In fact, everything has two sides. It will become easier as long as you work hard, believe in yourself. There are no shortcuts to learning, you can only rely on hard work, and if you are a programmer learning databases, you don’t need to know much, just know the basic operations. If you specialize in databases, you will need a lot more.
If you are learning language programming and learning databases, then the following will be enough:
First learn to add, delete, modify and check four statements,
Then learn to build databases, tables and constraints,
Then learn to modify the library to modify the table, delete the table, delete the column, delete the library,
Then learn things, indexes, views, and stored procedures
Also learn some case end statements while loop if judgment
There are also subquery groupings Query
Basically, it’s enough to know these, and the rest just need to be checked.
Hope it helps you.
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