MySQL 8 Administrator???s Guide

Optimizing MySQL data types

The following are the guidelines for optimizing numeric data types:

• Numeric columns must be preferred over string columns to store unique IDs or other values that can be represented as either strings or numbers. It is faster and occupies less memory to transfer and compare, because large numeric values are stored in fewer bytes compared to strings.
• It is faster to access information from a database than from a text file. This is especially true when numeric data is used. Information in the database is stored in a more compact format than in the text file. So, it requires fewer disk accesses.

The following are the guidelines for optimizing character and string data types:

• The binary collation order (logical sequence) ...