VECTOR_ADD

Adds two input vectors and returns a single vector blob.

It is a scalar function.

Syntax

VECTOR_ADD(vector_expression, vector_expression)

Arguments

  • vector_expression: An expression that evaluates to a vector. The vector must be encoded as a blob containing packed single-precision or double-precision floating-point numbers in little-endian byte order.

Return Type

A blob containing packed single-precision floating-point numbers in little-endian byte order.

Remarks

A vector can be of any length, but the input blob length must be divisible by the packed vector element size (1, 2, 4 or 8 bytes, depending on the vector element).

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

The following examples use the JSON_ARRAY_UNPACK() function to view the output in JSON format.

Adding Two Vectors

The following example uses the t table:

CREATE TABLE v_t (x BLOB, y BLOB);
INSERT INTO v_t VALUES (JSON_ARRAY_PACK('[12.1, 6.4]'), JSON_ARRAY_PACK('[8.6,9.2]'));
INSERT INTO v_t VALUES (JSON_ARRAY_PACK('[5.2, 11.7]'), JSON_ARRAY_PACK('[4.6,7.3]'));

This example adds two vector blobs using the VECTOR_ADD() function:

SELECT JSON_ARRAY_UNPACK(VECTOR_ADD(x,y)) "x+y" FROM v_t;
+-------------------------+
| x+y                     |
+-------------------------+
| [20.7000008,15.6000004] |
| [9.79999924,19]         |
+-------------------------+

The vector blobs are added as 32-bit floating point numbers because no suffix is specified with the VECTOR_ADD() function. You can also view the output vector blob in hexadecimal format using the HEX() function.

SELECT HEX(VECTOR_ADD(x,y)) "x+y" FROM v_t;
+------------------+
| x+y              |
+------------------+
| 9A99A5419A997941 |
| CCCC1C4100009841 |
+------------------+

Typecasting the Data Type Using Suffixes

To perform this operation on vectors specified in a format other than the default 32-bit floating point number, specify a suffix with the VECTOR_ADD() function. For example,

SELECT JSON_ARRAY_UNPACK_I16(VECTOR_ADD_I16(JSON_ARRAY_PACK_I16('[6,2]'),JSON_ARRAY_PACK_I16('[8,4]'))) AS "Result";
+--------+
| Result |
+--------+
| [14,6] |
+--------+

Last modified: March 8, 2024

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