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Welcome to the MySQL technical articles shared by the great SQL community. If you have any questions or want to learn, you can leave a message in the comment area below. After seeing it, you will answer itThis article introduces you to a method of sql syntax parsing and tracing using mysql parser and bison's debugging options.In the process of ...

I DDL – operating databases and tables 1. Query SHOW DATABASES; 2. Create Create database CREATE DATABASE Database name; Create database (judge, create if it does not exist) CREATE DATABASE IF NOT EXISTS Database name; 3. Delete Delete database DROP DATABASE Database name; Delete the database (judge, delete if it exists) ...

Welcome to the MySQL technical articles shared by the great SQL community. If you have any questions or want to learn, you can leave a message in the comment area below. After seeing it, you will answer itDifferent parameters added to lsof will produce different results. Be careful of "stepping on the pit".1. Background:It was acciden ...

Transaction It exists in both SQL server and Mysql It refers to the smallest unit to complete an application processing, which is composed of one or more statements operating on the database. If all operations are successful before submitting a failure, all operations will be cancelled and restored to the previous state. 1. Cases where transac ...

catalogue Low Medium High  Impossible SQL Injection (blind), that is, SQL blind injection, is different from general injection in that the general injection attacker can directly see the execution result of the injection statement from the page, while during blind injection, the attacker usually cannot obtain the execution result from the ...

Welcome to the MySQL technical articles shared by the great SQL community. If you have any questions or want to learn, you can leave a message in the comment area below. After seeing it, you will answer itproblemThe original question is as follows:If you add a shared lock to a row of a table in a MySQL transaction, in theory, the table itself w ...

preface: The article was first published in https://sleepymonster.cn This is a question for the finals of the 2021 Jinan University freshman competition. At that time, I was gambling. If I did it, I would win the second prize Unfortunately, the network is not powerful enough to suck out second times without changing the script. But I'v ...

         Mybatis plus (MP) is an enhancement tool for mybatis, so how is it enhanced? In fact, it has encapsulated some crud methods, so there is no need to write xml for development. Just call these methods directly, which is similar to JPA. The structure diagram of mybatis plus is as follows: Entry cla ...

🔎 MySQL notes Retrieve data Retrieve different rows select distinct vend_id from products Limit the result, that is, limit the number of rows output select prod_name from products LIMIT 4,5 //Indicates that five rows of data are retrieved from the fourth row. The first is the starting position and the second is the number of rows to be r ...

sql execution statement flow analysis The whole processing flow is in exec_simple_query function. The code structure is as follows: /* * exec_simple_query * * Execute a "simple Query" protocol message. */ static void exec_simple_query(const char *query_string) { ... //Original syntax tree acquisition /* * Do basic parsing of the quer ...