Booleans

Boolean values can be used to mark whether a field is true or false.

CREATE person SET newsletter = false, interested = true;

Many SurrealDB operators and functions return booleans.

CREATE person SET 
    name = "Billy", 
    name_is_billy = name = "Billy",
    name_is_long = string::len(name) > 10;

Response
[
    {
        "id": "person:8ii7v7f54a2m1rla1y6b",
        "name": "Billy",
        "name_is_billy": true,
        "name_is_long": false
    }
]

Boolean values can be written in anycase.

CREATE person SET 
    newsletter = FALSE,
    interested = True,
    very_interested = trUE;

Booleans in WHERE clauses

When performing a query on the database, accessing a record’s ID directly or using a record range allows performance to be significantly sped up by avoiding the table scan which is used when a WHERE clause is included.

However, if a WHERE clause is unavoidable, performance can still be improved by simplifying the portion after the clause as much as possible. As a boolean is the simplest possible datatype, having a boolean field that can be used in a WHERE clause can significantly improve performance compared to a more complex operation.

-- Fill up the database a bit with 10,000 records
CREATE |person:10000| SET
    random_data = rand::string(1000),
    data_length = random_data.len(),
    is_short = data_length < 10 RETURN NONE;
-- Add one outlier
CREATE person:one SET
    random_data = "HI!",
    data_length = random_data.len(),
    is_short = data_length < 10 RETURN NONE;

-- Function call + compare operation: slowest
SELECT * FROM person WHERE random_data.len() < 10;
-- Compare operation: much faster
SELECT * FROM person WHERE data_length < 10;
-- Boolean check: even faster
SELECT * FROM person WHERE is_short;
-- Direct record access: almost instantaneous
SELECT * FROM person:one;