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https://dev.mysql.com/doc/refman/8.4/en/retrieving-data.html
The SELECT statement is used to pull information from a table. The general form of the statement is: SELECT what_to_select FROM which_table WHERE conditions_to_satisfy; what_to_select indicates what you want to see. This can be a list of columns, ...
https://dev.mysql.com/doc/refman/8.4/en/rewriter-query-rewrite-plugin.html
MySQL supports query rewrite plugins that can examine and possibly modify SQL statements received by the server before the server executes them. MySQL distributions include a postparse query rewrite plugin named Rewriter and scripts for installing ...
https://dev.mysql.com/doc/refman/8.4/en/row-constructor-optimization.html
For example, these two statements are semantically equivalent: SELECT * FROM t1 WHERE (column1,column2) = (1,1); SELECT * FROM t1 WHERE column1 = 1 AND column2 = 1; In addition, the optimizer handles both expressions the same way. The optimizer is ...
https://dev.mysql.com/doc/refman/8.4/en/scalar-subqueries.html
In its simplest form, a subquery is a scalar subquery that returns a single value. A scalar subquery is a simple operand, and you can use it almost anywhere a single column value or literal is legal, and you can expect it to have those ...
https://dev.mysql.com/doc/refman/8.4/en/security-options.html
The following table shows mysqld options and system variables that affect security. For descriptions of each of these, see Section 7.1.7, “Server Command Options”, and Section 7.1.8, “Server System Variables”.
https://dev.mysql.com/doc/refman/8.4/en/selecting-all.html
For example, you may happen to think that the birth date for Bowser doesn't seem quite right. Consulting your original pedigree papers, you find that the correct birth year should be 1989, not 1979. Fix only the erroneous record with an UPDATE ...
https://dev.mysql.com/doc/refman/8.4/en/selecting-columns.html
If you do not want to see entire rows from your table, just name the columns in which you are interested, separated by commas.
https://dev.mysql.com/doc/refman/8.4/en/selecting-rows.html
As shown in the preceding section, it is easy to retrieve an entire table. But typically you don't want to see the entire table, particularly when it becomes large. Instead, you're usually more interested in answering a particular question, in ...
https://dev.mysql.com/doc/refman/8.4/en/selinux-file-context.html
The MySQL Server reads from and writes to many files. If the SELinux context is not set correctly for these files, access to the files could be denied. The instructions that follow use the semanage binary to manage file context; on RHEL, it's part ...
https://dev.mysql.com/doc/refman/8.4/en/serialized-dictionary-information.html
In addition to storing metadata about database objects in the data dictionary, MySQL stores it in serialized form. Other storage engines store SDI data in .sdi files that are created for a given table in the table's database directory. Serialized ...