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Home Database Mysql Tutorial What are the numeric types in mysql mysql numeric data types

What are the numeric types in mysql mysql numeric data types

May 28, 2025 pm 06:42 PM
mysql

Numeric types in MySQL are divided into integer types and floating point types. 1. Integer types include TINYINT, SMALLINT, MEDIUMINT, INT and BIGINT, which are suitable for integer storage in different ranges. 2. Float number types include FLOAT, DOUBLE and DECIMAL, which are suitable for floating point number storage with different precisions. DECIMAL is suitable for scenarios that require high precision.

What are the numeric types in mysql mysql numeric data types

In MySQL, numeric types are an integral part of database design. They are used to store numeric data, and there are corresponding types to choose from from integers to floating point numbers. Today we will talk about the numerical types in MySQL, as well as their respective characteristics and usage scenarios. Numeric types in MySQL are mainly divided into two categories: integer types and floating-point types. Let's explore these types one by one and see how they work in real-world applications. Integer types include TINYINT, SMALLINT, MEDIUMINT, INT, and BIGINT. These types are mainly used to store numbers without a fractional part. TINYINT can store values ??from -128 to 127, suitable for storing small integer data, such as status flags. SMALLINT has a larger range and can store values ??from -32768 to 32767, suitable for storing medium-sized integer data. MEDIUMINT can store values ??from -8388608 to 8388607, which is suitable for integer storage that requires a larger range. INT is the most commonly used integer type, which can store values ??from -2147483648 to 2147483647, suitable for the storage of most integer data. BIGINT provides the largest integer storage range, which can store values ??from -9223372036854775808 to 9223372036854775807, which is suitable for storing very large integer data. Float number types include FLOAT and DOUBLE, and DECIMAL types. The FLOAT type is used to store single-precision floating point numbers, occupying 4 bytes, and is suitable for storing floating point data that does not require high precision. The DOUBLE type is used to store double-precision floating-point numbers, occupying 8 bytes, and is suitable for storing floating-point data that requires higher precision. However, FLOAT and DOUBLE types may introduce rounding errors in stored procedures, which can be a problem in some scenarios where precise calculations are required. The DECIMAL type is different. It is used to store fixed-point numbers and can accurately store decimal parts. It is suitable for scenarios that require high-precision calculations, such as the storage of financial data. When selecting a numerical type, you need to consider the scope and accuracy requirements of the data. For example, if you need to store the user's age, the INT type may be enough. But if you are storing the user's account balance, the DECIMAL type is more appropriate because it ensures the accuracy of the data. In practical applications, I once encountered a project that needs to store user's points data. Since the points can be very large, we chose the BIGINT type to ensure that the data storage does not overflow. At the same time, we also need to store the user's consumption amount. At this time, we chose the DECIMAL(10, 2) type to ensure the accuracy of the amount data. When using these numerical types, you also need to pay attention to some common misunderstandings. For example, many developers tend to use FLOAT or DOUBLE to store amount data, but this may cause accuracy issues. In my project, we had some calculation errors because we used the FLOAT type to store the amount, and we eventually had to use the DECIMAL type instead. In addition, choosing the right numerical type can also affect the performance of the database. For example, fields of type TINYINT take up less storage space than fields of type INT, which can significantly reduce storage requirements and improve query performance when processing large-scale data. In short, there are a wide variety of numerical types in MySQL. Choosing the right type can not only ensure the correct storage of data, but also optimize the performance of the database. In practical applications, it is very important to choose the right type according to the specific needs of the data.

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