Data Types and Forms

Data Type Mappings

The following table shows the mapping between data types in C++ and their corresponding data types in DolphinDB (“-“ indicates that there is no matching C++ data type).

Category	DolphinDB Data Type	DolphinDB Example	C++ Data Type	C++ Example
NUMERIC	BOOL	false	char	0
	CHAR	’a'	char	'a'
	SHORT	122h	short	122
	INT	21	int	21
	LONG	22l	long long	22
	FLOAT	2.1f	float	2.1f
	DOUBLE	2.2	double	2.2
	DECIMAL32	decimal32(2.1, 3)	int	2100
	DECIMAL64	decimal64(2.1, 3)	long	2100
	DECIMAL128	decimal128(2.1, 3)	int128	2100
TEMPORAL	DATE	2013.06.13	int	15869
	MONTH	2012.06M	int	24149
	TIME	13:30:10.008	int	48610008
	MINUTE	13:30m	int	810
	SECOND	13:30:10	int	48610
	DATETIME	2012.06.13 13:30:10	int	1339594210
	DATEHOUR	2012.06.13T13	int	372109
	TIMESTAMP	2012.06.13 13:30:10.008	long long	1339594210008
	NANOTIME	13:30:10.008007006	long long	48610008007006
	NANOTIMESTAMP	2012.06.13 13:30:10.008007006	long long	1339594210008007006
LITERAL	STRING	“Hello”	std::string	“Hello”
	SYMBOL	“Hello”	-	-
	BLOB	“Hello”	std::string	“Hello”
OTHER	UUID	5d212a78-cc48-e3b1-4235-b4d91473ee87	unsigned char[16]	-
	INT128	e1671797c52e15f763380b45e841ec32	unsigned char[16]	-
	IPADDR	192.168.1.13	unsigned char[16]	-
	VOID	NULL	-	-

Supported Data Forms

The DolphinDB C++ API supports various data forms, which are listed below with examples of DolphinDB data forms.

Data Form	Description	DolphinDB Example
scalar	a variable that holds one value at a time	5, 1.3, 2012.11.15, `hello
vector	a container that holds a list of objects in a given order	[1,2,3,4,5,6,7,8,9,10]
array vector	a two-dimensional vector where each row is a variable-length vector	[[1,2,3],[4,5],[6,7,8],[9,10]]
matrix	a one-dimensional array with column major	matrix([1 2 3, 4 5 6]);
set	a container that holds a list of unsorted objects with no duplicate values	(2,5)
dictionary	a container that holds a list of unique key-value pairs	(1->4.5, 2->7.8, 3->4.3)
table	a database object that holds a list of vectors in a given order	-