The meaning of double expression in mysql

The DOUBLE data type in MySQL is a 64-bit floating point number, used to store high-precision floating point numbers. Features include: 1. Accuracy up to 15-16 significant digits; 2. Value range is -1.7976931348623157e 308 to 1.7976931348623157e 308; 3. Occupies 8 bytes of storage space. Suitable for scenarios that require high-precision floating point operations, such as scientific computing, financial modeling and statistical analysis.

DOUBLE data type in MySQL

Definition
In MySQL, DOUBLE The data type is a large-precision data type used to store floating point numbers. It is a 64-bit floating point number capable of representing very large or very small numbers.

Features

• Precision: The DOUBLE data type has a precision of 15-16 significant digits, which means it can store up to 15-16 decimal places.
• Range: The value range of the DOUBLE data type is -1.7976931348623157e 308 to 1.7976931348623157e 308. Values ​​exceeding this range will be rounded to the nearest DOUBLE value.
• Storage space: DOUBLE data type occupies 8 bytes of storage space.

Usage scenarios

The DOUBLE data type is usually used to store scenarios that require high-precision floating point operations, such as:

• Scientific Computing and Engineering Applications
• Financial and Economic Modeling
• Statistical Analysis and Data Mining

Notes

• For scenarios with low accuracy requirements, it is recommended to use the FLOAT data type because it takes up less storage space.
• The DOUBLE data type may suffer from rounding errors when performing mathematical operations, so it should be used with caution in scenarios that require absolute precision.
• For scenarios that require a fixed number of decimal places to store currency values, it is recommended to use the DECIMAL data type.

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