Learning Apache Cassandra(Second Edition)
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Floating point and decimal numbers

Cassandra has three types that store non-integer numbers:

  • The float type stores 32-bit IEEE-754 floating point numbers.
  • The double type stores 64-bit IEEE-754 floating point numbers.
  • The decimal type stores variable-precision decimal numbers, with no upper bound on size. Unlike a floating point number, a variable-precision decimal will never suffer from base 10 rounding errors in the fractional part of the number.

Like the integer types, the floating point and decimal types are always signed. In CQL, floating point and decimal literals are represented by an optional minus sign, followed by a series of digits, followed by a period, followed by another series of digits, such as 7,152.6846. You can also write them using exponential notation, such as 9.021e14.