The DECIMAL data type in MySQL is used to store exact decimal numbers with a decimal point. Features include: Precision: specified by number of digits and fixed number of decimal places. Range: Allows storing large or small decimal values, depending on precision. Precision Guarantee: Unlike floating point types, DECIMAL is guaranteed to store the exact value, avoiding rounding errors. Syntax: DECIMAL(precision, scale), precision specifies the total number of digits, and scale specifies the number of decimal places. Usage scenarios: monetary calculations, measurement, science, finance and accounting, etc. where precise calculations are required.
DECIMAL in MySQL
The DECIMAL data type is used to store fixed-precision decimal numbers with a decimal point. It is a precise numeric type used where precise numerical calculations are required.
Features:
- Precision: is specified by two parts, the number of digits (total length) and the number of decimal places.
- Range: Allows storing very large or very small decimal values, depending on precision.
- Precision guarantee: Unlike floating point types (such as FLOAT and DOUBLE), DECIMAL is guaranteed to store an exact value, unaffected by rounding errors.
Syntax:
<code>DECIMAL(precision, scale)</code>
- precision: Specify the total number of digits (including decimal points).
- scale: Specify the number of decimal places.
Example:
<code>DECIMAL(10, 2)</code>
This example defines a DECIMAL data type with a total length of 10 digits and a scale of 2 digits.
Usage scenarios:
DECIMAL data type is usually used in the following scenarios:
- Currency calculation: Storage amount Or monetary values that require precise calculation, such as prices.
- Measurement and Science: Storage values that require accuracy such as measurements or calculation results.
- Finance and Accounting: Store transaction amounts, balances and other financial data that need to be calculated accurately.
Note:
- The DECIMAL data type takes up more storage space than the floating-point data type.
- For scenarios that do not require precise calculations, you can use the FLOAT or DOUBLE data type.
- The appropriate DECIMAL precision should be chosen based on actual precision requirements to avoid storing unnecessary data or rounding errors.
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