TINYINT Data Type

A 1-byte integer data type used in CREATE TABLE and ALTER TABLE statements.

Syntax:

In the column definition of a CREATE TABLE statement:

column_name TINYINT

Range: -128 .. 127. There is no UNSIGNED subtype.

Conversions: Impala automatically converts to a larger integer type (SMALLINT, INT, or BIGINT) or a floating-point type (FLOAT or DOUBLE) automatically. Use CAST() to convert to STRING or TIMESTAMP. Casting an integer or floating-point value N to TIMESTAMP produces a value that is N seconds past the start of the epoch date (January 1, 1970).

Impala does not return column overflows as NULL, so that customers can distinguish between NULL data and overflow conditions similar to how they do so with traditional database systems. Impala returns the largest or smallest value in the range for the type. For example, valid values for a tinyint range from -128 to 127. In Impala, a tinyint with a value of -200 returns -128 rather than NULL. A tinyint with a value of 200 returns 127.

Usage notes:

For a convenient and automated way to check the bounds of the TINYINT type, call the functions MIN_TINYINT() and MAX_TINYINT().

If an integer value is too large to be represented as a TINYINT, use a SMALLINT instead.

NULL considerations: Casting any non-numeric value to this type produces a NULL value.

Examples:

CREATE TABLE t1 (x TINYINT);
SELECT CAST(100 AS TINYINT);

Parquet considerations:

Physically, Parquet files represent TINYINT and SMALLINT values as 32-bit integers. Although Impala rejects attempts to insert out-of-range values into such columns, if you create a new table with the CREATE TABLE ... LIKE PARQUET syntax, any TINYINT or SMALLINT columns in the original table turn into INT columns in the new table.

HBase considerations: This data type is fully compatible with HBase tables.

Text table considerations: Values of this type are potentially larger in text tables than in tables using Parquet or other binary formats.

Internal details: Represented in memory as a 1-byte value.

Added in: Available in all versions of Impala.

Column statistics considerations: Because this type has a fixed size, the maximum and average size fields are always filled in for column statistics, even before you run the COMPUTE STATS statement.

Related information:

Numeric Literals, TINYINT Data Type, SMALLINT Data Type, INT Data Type, BIGINT Data Type, DECIMAL Data Type (CDH 5.1 or higher only), Impala Mathematical Functions