double precision number

基本解释

Gets the value of the column as a double-precision floating point number.
指定的列不包含双精度浮点数。
Regan speculated that this particular number is troublesome because it is the "largest subnormal double-precision floating-point number."
Regan 推测这个特殊数字的麻烦之处在于它是“最大的次法线双精度浮点数”。
The DOUBLE type can also be referred to as DOUBLE PRECISION, although it isn't clear why you would want to type the extra word every time you need a double-precision number.
DOUBLE 类型也可以表示为 DOUBLE PRECISION，虽然为什么在需要双精度数字时要输入额外的单词，原因不明。