• MapReduce Service

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  4. Using MRS
  5. Using CarbonData
  6. About CarbonData Table

About CarbonData Table

Overview

CarbonData tables are similar to tables in the relational database management system (RDBMS). RDBMS tables consist of rows and columns to store data. CarbonData tables have fixed columns and also store structured data. In CarbonData, data is saved in entity files.

Data Types Supported

CarbonData tables support the following data types:

  • Int
  • String
  • BigInt
  • Decimal
  • Double
  • TimeStamp

Table 1 describes the details about the data types.

Table 1 CarbonData data types

Data Type

Description

Int

4-byte signed integer ranging from -2,147,483,648 to 2,147,483,647

NOTE:

If non-dictionary columns have Int data, the data is saved as BigInt data in the table.

String

The maximum character string length is 100,000.

BigInt

Data is saved using the 64-bit technology. The value ranges from -9,223,372,036,854,775,808 to 9,223,372,036,854,775,807.

Decimal

The default value is (10,0) and maximum value is (38,38).

NOTE:

If a query condition is used, users can add BD after the number to obtain accurate results. For example, select * from carbon_table where num = 1234567890123456.22BD.

Double

Data is saved using the 64-bit technology. The value ranges from 4.9E-324 to 1.7976931348623157E308.

TimeStamp

The default format is yyyy-MM-dd HH:mm:ss.

NOTE:

Measurement of all Int data is processed and displayed using the BigInt data type.