与普通的decimal类型不同,不给定限制的decimal类型允许存储任意长度的小数,并且不会因为数据超出指定范围而发生截断或溢出。 下面是一个使用不给定限制的decimal类型的示例: CREATETABLEexample(idINTPRIMARYKEYAUTO_INCREMENT,valueDECIMAL);INSERTINTOexample(value)VALUES(123.45678901234567890123456789012345678901234567890); 1. ...
For example, aDECIMAL(18,9)column has nine digits on either side of the decimal point, so the integer part and the fractional part each require 4 bytes. ADECIMAL(20,6)column has fourteen integer digits and six fractional digits. The integer digits require four bytes for nine of the digits...
As of MySQL 8.0.17, the UNSIGNED attribute is deprecated for columns of type FLOAT, DOUBLE, and DECIMAL (and any synonyms) and will be removed in a future MySQL version. Consider using a simple CHECK constraint instead for such columns. 从8.0.17版本开始,UNSIGNED属性对于FLOAT、DOUBLE、DECIMAL(...
关键字INT是INTEGER的同义词，关键字DEC是DECIMAL的同义词。BIT数据类型保存位字段值，并且支持 MyISAM、...
http://dev.mysql.com/doc/refman/5.7/en/data-type-overview.html mysql常用数据类型概览 代码语言:javascript 复制 #1. 数字: 整型:tinyinit int bigint 小数: float :在位数比较短的情况下不精准 double :在位数比较长的情况下不精准 0.000001230123123123 存成:0.000001230000 decimal:(如果用小数,则用推荐使用...
Two numbers that look similar may be treated differently. For example,2.34is an exact-value (fixed-point) number, whereas2.34E0is an approximate-value (floating-point) number. TheDECIMALdata type is a fixed-point type and calculations are exact. In MySQL, theDECIMALtype has several synonyms:NU...
http://dev.mysql.com/doc/refman/5.7/en/data-type-overview.html mysql常用数据类型概览 #1. 数字: 整型:tinyinit int bigint 小数: float :在位数比较短的情况下不精准 double :在位数比较长的情况下不精准 0.000001230123123123 存成:0.000001230000 decimal:(如果用小数,则用推荐使用decimal) 精准 内部原理是...
DECIMAL类型 DECIMAL类型用于存储定点数,即具有固定小数位数的小数。它可以用于存储较为精确的小数值,例如货币金额。DECIMAL类型的存储空间和精度由用户指定。 示例: 代码语言:javascript 复制 CREATETABLEexample(idINTNOTNULLAUTO_INCREMENT,priceDECIMAL(10,2)NOTNULL,PRIMARYKEY(id)); ...
1. 将Float数据类型转换为Double或Decimal数据类型,Decimal数据类型会保留准确精确度数据,而使用Double时不存在该问题。 2. 为Float指定长度和小数位数 3. 使用FORMAT函数进行转换,如WHERE FORMAT(C1,3)=FORMAT(123.456,3) 4. 使用Like进行匹配,如WHERE C1 LIKE 123.456 ...
DECIMALandNUMERICtypes store exact numeric data values. These types are used when it is important to preserve exact precision, for example with monetary data. In MySQL,NUMERICis a synonym forDECIMAL. Floats, doubles, and decimals may have specified their precision and scale. InDECIMAL[M, D]the...