Important

The SingleStore 10 release candidate (RC) gives you the opportunity to preview, evaluate, and provide feedback on new and upcoming features prior to their general availability. In the interim, SingleStore 9.0 is recommended for production workloads, which can later be upgraded to SingleStore 10.

VECTOR_SUBVECTOR

Syntax

SQL

VECTOR_SUBVECTOR(vector_expression, start_position, length)

Arguments

vector_expression: An expression that evaluates to a vector. The input expression can use the VECTOR data type or a BLOB-encoded vector.
start_position: A 0-indexed number to determine where to start count. A positive index counts from the beginning of the vector. A negative index counts from the end of the vector.
length: Length of required subvector.

Return Type

If the input expression is of type VECTOR, VECTOR_SUBVECTOR() returns a VECTOR expression.
If the input expression is of type BLOB, VECTOR_SUBVECTOR() returns a BLOB.

Remarks

If the input is NULL, NULL will be returned.

You can specify the data type of the vector elements in which this operation is performed on the vector by adding a suffix to the function. Omitting the suffix from the function is equivalent to suffixing it with _F32. All operations are done using the specified data type. The following table lists the suffixes and their data type.

Suffix	Data Type
`_I8`	8-bit signed integer
`_I16`	16-bit signed integer
`_I32`	32-bit signed integer
`_I64`	64-bit signed integer
`_F32`	32-bit floating-point number (IEEE standard format)
`_F64`	64-bit floating-point number (IEEE standard format)

Examples

SQL

CREATE TABLE vsv_t (x BLOB);
INSERT INTO vsv_t VALUES (JSON_ARRAY_PACK('[1,2,3,4,5]'));

SQL

SELECT JSON_ARRAY_UNPACK (VECTOR_SUBVECTOR(x,2,2)) AS x from vsv_t;

+-------+
| x     |
+-------+
| [3,4] |
+-------+

SQL

SELECT JSON_ARRAY_UNPACK (VECTOR_SUBVECTOR(x,-2,2)) AS x from vsv_t;

+-------+
| x     |
+-------+
| [4,5] |
+-------+

How to Use the Vector Data Type

When the input expression uses the VECTOR data type, VECTOR_SUBVECTOR() returns the selected subvector as a VECTOR expression. VECTOR_SUBVECTOR() accepts VECTOR inputs of all supported element types, including F16 (for example, VECTOR(5, F16)). For readable output, set vector_type_project_format to JSON.

Example

SQL

SET @pos = '[1,2,3,4]':>VECTOR(4);

SELECT VECTOR_SUBVECTOR(@pos, 1, 2):>VECTOR(2);
+----------------------------------+
| VECTOR_SUBVECTOR(@pos, 1, 2):>VECTOR(2) |
+----------------------------------+
| [2,3]                            |
+----------------------------------+