Data Type Conversions
The general rule is to follow the CAST function if defined. If CAST is not defined, then all input data is treated as a string. It must be cast into the relevant data types when necessary.

For more information about the CAST function, see CAST.

Supported Data Types
Amazon S3 Select supports the following set of primitive data types.

Name Description Examples
bool TRUE or FALSE FALSE
int, integer 8-byte signed integer in the range -9,223,372,036,854,775,808 to 9,223,372,036,854,775,807. 100000
string UTF8-encoded variable-length string. The default limit is one character. The maximum character limit is 2,147,483,647. 'xyz'
float 8-byte floating point number. CAST(0.456 AS FLOAT)
decimal, numeric

Base-10 number, with maximum precision of 38 (that is, the maximum number of significant digits), and with scale within the range of -231 to 231-1 (that is, the base-10 exponent).

Note
Amazon S3 Select ignores scale and precision when you provide both at the same time.

123.456
timestamp

Time stamps represent a specific moment in time, always include a local offset, and are capable of arbitrary precision.

In the text format, time stamps follow the W3C note on date and time formats, but they must end with the literal "T" if not at least whole-day precision. Fractional seconds are allowed, with at least one digit of precision, and an unlimited maximum. Local-time offsets can be represented as either hour:minute offsets from UTC, or as the literal "Z" to denote a local time of UTC. They are required on time stamps with time and are not allowed on date values.

CAST('2007-04-05T14:30Z' AS TIMESTAMP)
Supported Parquet types
Amazon S3 Select supports the following Parquet types.

DATE

DECIMAL

ENUM

INT(8)

INT(16)

INT(32)

INT(64)

LIST

Note
For LIST Parquet type output, Amazon S3 Select only supports JSON format. However, if the query limits the data to simple values, the LIST Parquet type can also be queried in CSV format.

STRING

TIMESTAMP supported precision (MILLIS/MICROS/NANOS)

Note
Timestamps saved as an INT(96) are unsupported.

Due to the range of the INT(64) type, timestamps using the NANOS unit can only represent values between 1677-09-21 00:12:43 and 2262-04-11 23:47:16. Values outside of this range cannot be represented with the NANOS unit.

Mapping of Parquet types to supported data types in Amazon S3 Select
Parquet types Supported data types
DATE

timestamp

DECIMAL

decimal, numeric

ENUM

string

INT(8)

int, integer

INT(16)

int, integer
INT(32) int, integer
INT(64)

decimal, numeric

LIST

Each Parquet type in list is mapped to the corresponding data type

STRING

string

TIMESTAMP

timestamp