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Editor to share with you what are the advantages and disadvantages of mysql cursors, I believe most people do not know much about it, so share this article for your reference, I hope you can learn a lot after reading this article, let's go to know it!

Introduction to Vernier

MySQL cursor (cursor) is an important concept, by looking for information and their own understanding, mainly draw the following points about their own understanding.

The idea of data buffering: the design of cursors is the idea of a data buffer, which is used to store the results of the execution of SQL statements.

Data base: cursors are techniques that can continue to operate flexibly after the data is retrieved from the data table.

Similar to pointers: cursors are similar to pointers in the data structure stack, used to pop the data they point to, and can only be fetched one at a time.

Advantages and disadvantages of cursors:

(1) the advantages of cursors:

Because cursors operate on rows, it is a separate idea to perform separate, identical or different operations on each row obtained from a select query in the database. It can satisfy a special operation on a result row. Cursor and the ability to add, delete, change and search based on the position of the cursor. MySQL database does not specifically describe the expression of a row, but this is necessary, so, as far as I understand it, I think cursors are extracted from the set-oriented system of relational database and expressed separately for rows (it can also be understood as online materials: cursors are a bridge between set-oriented and line-oriented design ideas).

(2) shortcomings of cursors

The disadvantage of the cursor is for a point, that is, it can only operate one by one, which is not applicable in the case of a large amount of data, and the speed is too slow. Here is an analogy: when you go to ATM to save money, do you want to save it all at once, or a deposit of 100th sheet, which is the operation of the cursor for the line? Most of the database is facing the collection, the business will be more complex, and the use of cursors will have deadlocks, affecting other business operations, which is not desirable. When the amount of data is large, the use of cursors will cause insufficient memory.

These are all the contents of the article "what are the advantages and disadvantages of mysql cursors?" Thank you for reading! I believe we all have a certain understanding, hope to share the content to help you, if you want to learn more knowledge, welcome to follow the industry information channel!

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