What are the applications of the SQL CAST function?

The CAST function in SQL is used to convert one data type to another data type. Its use cases include:

1. Data type conversion: changing one data type to another, such as converting a string to an integer or an integer to a date.
2. Data formatting: The process of arranging data in a specific format, such as converting dates into a specific string format.
3. Data comparison: The CAST function can be used to compare values of different data types, such as converting string type numbers to integers before comparing them.
4. Data calculation: In some calculations, it is necessary to convert values of different data types before performing operations, such as converting string-type numbers to integers before addition, subtraction, multiplication, or division.
5. Data visualization: In reports or query results, it is necessary to convert the data types of certain fields or expressions to meet the display requirements.

In general, the CAST function in SQL queries can be used to convert, format, compare, and calculate data, providing more flexible data processing capabilities.