Supported Data Types

This page provides details on the data types used within KDB.AI tables, including name, range/example, brief description, and usage.

In KDB.AI, tables are fundamental structures for storing and organizing data. A schema is a list of column definitions that defines the structure of a table. Each column holds data of a specific type, such as integers, symbols, or dates.

Here’s a list of supported data types (scalar and list) in KDB.AI tables:

Datatype	q Type (scalar/list)	JSON Type (scalar/list)	Python (scalar/list)	Example/Range	Description	Usage
boolean	b / B	boolean / booleans	bool / bools	true, false	Represents true or false values	Used for binary conditions and flags
byte	x / X	byte / bytes	uint8 / uint8s	0 to 255	8-bit unsigned integer	Used for raw binary data
char	c / C	char / chars	char / bytes	'a', 'b', 'c'	Single character	Used for single character data
date	d / D	date / dates	datetime64[D] / datetime64[D]s	2024.10.30	Calendar date	Used for date-specific data
float	f / F	float / floats	float64 / float64s	3.14, 2.718	Double-precision floating-point number	Used for high-precision numerical data
guid	g / G	guid / guids	guid / guids	123e4567-e89b-12d3-a456-426614174000	Globally unique identifier	Used for unique identification
int	i / I	int / ints	int32 / int32s	-2147483648 to 2147483647	32-bit signed integer	Used for general integer data
long	j / J	long / longs	int64 / int64s	-9223372036854775808 to 9223372036854775807	64-bit signed integer	Used for large integer data
minute	u / U	minute / minutes	timedelta64[m] / timedelta64[m]s	12:34	Time duration in minutes	Used for time intervals
month	m / M	month / months	datetime64[M] / datetime64[M]s	2024.10	Year and month	Used for monthly data
real	e / E	real / reals	float32 / float32s	3.14, 2.718	Single-precision floating-point number	Used for numerical data with less precision
second	v / V	second / seconds	timedelta64[s] / timedelta64[s]s	12:34:56	Time duration in seconds	Used for time intervals
short	h / H	short / shorts	int16 / int16s	-32768 to 32767	16-bit signed integer	Used for smaller integer data
symbol	s / S	symbol / symbols	str	AAPL, GOOG	Interned string	Used for categorical data
time	t / T	time / times	timedelta64[ms] / timedelta64[ms]s	12:34:56.789	Time of day with millisecond precision	Used for time-specific data
timestamp	p / P	timestamp / timestamps	datetime64[ns] / datetime64[ns]s	2024.10.30T12:34:56.789	Date and time with nanosecond precision	Used for precise date-time data
timespan	n / N	timespan / timespans	timedelta64[ns]	1234567890ns	Time duration with nanosecond precision	Used for high-precision time intervals

Database types and JSON formats

For data ingestion, use the corresponding JSON formats for database types as below:

Database type ID	Database type name	JSON data format	Description	Example
-1h	boolean	Boolean	A Boolean literal of true or false	true
-2h	guid	String	A 36 character UUIDv4 formatted String	"77579e36-71e7-d395-5551-5a4221e86e2b"
-4h	byte	String	A 2 character hex string	ff
-5h	short	Number	A 16 bit number	32767
-6h	int	Number	A 32 bit number	2147483647
-7h	long	Number	A 64 bit number	4611686018427387904
-8h	real	Number	A 32 bit floating point number	3.14159265
-9h	float	Number	A 64 bit floating point number	3.14159265
-10h	char	String	A string of a single character	"a"
-11h	symbol	String	A string representing a symbol	"BTC"
-12h	timestamp	String	A ISO date-time without an offset in format 'yyyy-MM-dd'T'HH:mm:ss' with optional 0-9 decimals for nanoseconds	"2023-01-01T00:00:00.000000000"
-13h	month	String	A string representing a month in format MM-dd	"2023-10"
-14h	date	String	A string representing an ISO Date without an offset in format yyyy-MM-dd	"2023-10-01"
-15h	datetime	String	A ISO date-time without an offset in format 'yyyy-MM-dd'T'HH:mm:ss' with optional 0-3 decimals for milliseconds	"2023-01-01T00:00:00.000"
-16h	timespan	String	A duration of time with units in nanoseconds 'd'D'HH:mm:ss' with optional 0-9 decimals for nanoseconds	"0D00:00:00.000000005"
-17h	minute	String	A duration of time in HH:mm	"22:59"
-18h	second	String	A duration of time in HH:mm:ss	"22:59:13"
-19h	time	String	A duration fo time in HH:mm:ss with optional 0-9 decimals for nanosecond precision	"22:59:13.000000000"
1h	booleans	Array<Boolean>	Array of boolean values	[true, false]
2h	guids	Array<String>	Array of guid values	["09c4f826-b3f2-e699-c7ff-5195d89a0925", "c0b9ec94-87b6-b0e9-3427-312d62aaec9c"]
4h	bytes	Array<String>	Array of byte values	["ff", "0e"]
5h	shorts	Array<Number>	Array of short values	[32767, -32767]
6h	ints	Array<Number>	Array of int values	[2147483647, -2147483647]
7h	longs	Array<Number>	Array of long values	[4611686018427387904, -4611686018427387904]
8h	reals	Array<Number>	Array of real values	[1.1, 1.2]
9h	floats	Array<Number>	Array of float values	[1.1, 1.2]
10h	string	String	A string of text	"abcdef"
11h	symbols	Array<String>	Array of symbol values	["BTC","MSFT"]
12h	timestamps	Array<String>	Array of timestamp values	["2023-01-01T00:00:00.000000000", "2023-01-02T00:00:00.000000000"]
13h	months	Array<String>	Array of month values	["2023-10", "2023-11"]
14h	dates	Array<String>	Array of date values	["2023-10-01", "2023-10-02"]
15h	datetimes	Array<String>	Array of datetime values	["2023-01-01T00:00:00.000", "2023-01-02T00:00:00.000"]
16h	timespans	Array<String>	Array of timespan values	["0D00:00:00.000000005", "0D00:00:00.000000006"]
17h	minutes	Array<String>	Array of minute values	["22:59", "23:00"]
18h	seconds	Array<String>	Array of second values	["22:59:13", "22:59:14"]
19h	times	Array<String>	Array of time values	["22:59:13.000000000", "2023-01-01T00:00:00.001"]