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:7j4t4higwb141v1v2xum,
		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.

DEFINE FIELD data_length ON person VALUE random_data.len();
DEFINE FIELD is_short ON person VALUE random_data.len() < 10;

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