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https://dev.mysql.com/doc/refman/8.4/en/examples.html
Here are examples of how to solve some common problems with MySQL. Some of the examples use the table shop to hold the price of each article (item number) for certain traders (dealers). Supposing that each trader has a single fixed price per ...
https://dev.mysql.com/doc/refman/8.4/en/floating-point-types.html
MySQL performs rounding when storing values, so if you insert 999.00009 into a FLOAT(7,4) column, the approximate result is 999.0001. The FLOAT and DOUBLE types represent approximate numeric data values. MySQL uses four bytes for single-precision ...
https://dev.mysql.com/doc/refman/8.4/en/full-text-adding-collation.html
Warning User-defined collations are deprecated; you should expect support for them to be removed in a future version of MySQL. The server issues a warning for any use of COLLATE user_defined_collation in an SQL statement; a warning is also issued ...
https://dev.mysql.com/doc/refman/8.4/en/geometry-well-formedness-validity.html
Syntactic well-formedness is also checked for attempts to store geometries into tables. It is permitted to insert, select, and update geometrically invalid geometries, but they must be syntactically well-formed. For geometry values, MySQL ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-benefits.html
If you split up related data into different tables, you can set up foreign keys that enforce referential integrity. Inserts, updates, and deletes are optimized by an automatic mechanism called change buffering. InnoDB tables have the following ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-compression-tuning-monitoring.html
To dig deeper into performance considerations for compressed tables, you can monitor compression performance at runtime using the Information Schema tables described in Example 17.1, “Using the Compression Information Schema Tables”. A large ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-init-startup-configuration.html
On systems with a large amount of memory, you can improve concurrency by dividing the buffer pool into multiple buffer pool instances. If you have transactions that update, insert, or delete many rows, you might consider increasing the size of the ... The first decisions to make about InnoDB configuration involve the configuration of data files, log files, page size, and memory buffers, which should be configured before initializing ...
https://dev.mysql.com/doc/refman/8.4/en/keywords.html
Certain keywords, such as SELECT, DELETE, or BIGINT, are reserved and require special treatment for use as identifiers such as table and column names. This may also be true for the names of built-in functions. Some keywords which are otherwise ...
https://dev.mysql.com/doc/refman/8.4/en/limit-optimization.html
If you need only a specified number of rows from a result set, use a LIMIT clause in the query, rather than fetching the whole result set and throwing away the extra data. MySQL sometimes optimizes a query that has a LIMIT row_count clause and no ...
https://dev.mysql.com/doc/refman/8.4/en/log-destinations.html
For users who have access to the .CSV files that contain log table data, the files are easy to import into other programs such as spreadsheets that can process CSV input. INSERT, DELETE, and UPDATE cannot be used on a log table. MySQL Server ...