The SCALAR_VECTOR_MUL function multiples each element in a vector with a scalar value. The function returns a vector.


SCALAR_VECTOR_MUL(scalar_value, vector_expression)


  • scalar_value: A scalar value.

  • vector_expression: An expression that evaluates to a vector. Vectors can be stored in SingleStore using the BLOB type (BLOB Types).

Return Type

The function returns the type of the second argument.

Using SCALAR_VECTOR_MUL with Vectors as BLOBs

The following examples and descriptions show the use of SCALAR_VECTOR_MUL to multiply the a vector by a scalar when the elements of the vector are stored as a BLOB.

Example 1 - BLOB Argument

Create a table with a column of type BLOB to store the vectors. The second column in this table, with column name vec and type BLOB, will store the vectors. This example demonstrates storing vector data using BLOBs, hence the column of type BLOB named vec.

Then use the JSON_ARRAY_PACK built-in function to easily insert properly formatted vectors.

CREATE TABLE vectors_b (id int, vec BLOB not null);
INSERT INTO vectors_b VALUES (1, JSON_ARRAY_PACK('[0.1, 0.8, 0.2, 0.555]')); 
INSERT INTO vectors_b VALUES (2, JSON_ARRAY_PACK('[0.45, 0.55, 0.495, 0.5]'));

The following query multiples the vectors in the vectors_b table by 10 and uses JSON_ARRAY_UNPACK to see the results in JSON format.

FROM vectors_b
| id   | scalar_mul             |
|    1 | [1,8,2,5.55000019]     |
|    2 | [4.5,5.5,4.94999981,5] |

JSON_ARRAY_UNPACK was used here to output the vectors in readable format because VECTOR_SORT returns a BLOB when its second argument is a BLOB.

The following query multiples the vectors in the vectors_b table by 10 and uses HEX to view the results in hexadecimal format.

SELECT id, HEX(SCALAR_VECTOR_MUL(10, vec)) as scalar_mul
FROM vectors_b
| id   | scalar_mul                       |
|    1 | 0000803F00000041000000409A99B140 |
|    2 | 000090400000B04066669E400000A040 |

Using Suffixes for Other Element Types with BLOBs

The default element type for vector storage and processing is 32-bit floating point (F32). However, other element types are supported.

You can specify the datatype of the vector elements to be used in the operation by adding a suffix to the function. All operations are done using the specified datatype. Omitting the suffix from the function is equivalent to suffixing it with _F32.

When using a suffix, the return type will be the type of the suffix.

The following table lists the suffixes and their data type.


Data Type


8-bit signed integer


16-bit signed integer


32-bit signed integer


64-bit signed integer


32-bit floating-point number (IEEE standard format)


64-bit floating-point number (IEEE standard format)

Example 2 - BLOBs with 16-bit Integers

Below is an example of using JSON_ARRAY_PACK and SCALAR_VECTOR_MUL with 16-bit signed integers.

First create a table of vectors stored as 16-bit integers. Note the use of the _I16 suffix on JSON_ARRAY_PACK.

CREATE TABLE vectors_b_i (id int, vec BLOB not null);
INSERT INTO vectors_b_i VALUES (1, JSON_ARRAY_PACK_I16('[1, 3, 2, 5]')); 
INSERT INTO vectors_b_i VALUES(2, JSON_ARRAY_PACK_I16('[23, 4, 1, 8]'));

This following query multiplies the vectors in the vectors_b_i table by the scalar 10.

FROM vectors_b_i
| id   | scalar_mul      |
|    1 | [10,30,20,50]  |
|    2 | [230,40,10,80] |


Be sure that the suffixes you use to pack the vector data match the suffixes you use to unpack the data and the suffixes you use on functions to process that data.

Formatting Binary Vector Data for BLOBs

When using the BLOB type for vector operations, vector data can be formatted using JSON_ARRAY_PACK. If your vector data is already in a packed binary format, you can load that data into the BLOBs. The data must be encoded as a BLOB containing packed numbers in little-endian byte order. Vectors stored as BLOBs can be of any length; however, the input blob length must be divisible by the size of the packed vector elements (1, 2, 4 , or 8 bytes, depending on the vector element).

Last modified: June 6, 2024

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