Values & Expressions

Truthy/Falsy Expressions

A standalone key without an operator checks if the field has a truthy value:

active
message and status

A value is considered falsy if it is:

• null / None / missing
• Empty string ""
• Zero 0
• Boolean false

Everything else is truthy.

Use not to check for falsy values:

not archived          # archived is falsy
active and not debug  # active is truthy, debug is falsy

String Values

Without Spaces

If the value contains no spaces, write it directly:

status=200
host=prod-api-01
level=error

With Spaces

Enclose values with spaces in single or double quotes:

user="John Doe"
message='connection refused'

Escaping Quotes

If the value contains the same quote character used for enclosure, escape it with a backslash:

user='John\'s account'
message="said \"hello\""

Numeric Values

Numeric values are written without quotes:

status=200
duration>1000
count<=50

Numbers are used with all comparison operators (=, !=, >, >=, <, <=).

Whitespace

FlyQL is whitespace-tolerant. Spaces around operators are optional:

status=200          # no spaces
status = 200        # spaces around operator
status =200         # space before only

All of the above are equivalent. Whitespace between tokens is always allowed.

Examples

# Truthy check
active

# Negated truthy
not archived

# Unquoted string value
level=error

# Quoted string with spaces
user="John Doe"

# Numeric comparison
status>=400 and duration<5000

# Mixed
active and level=error and message~"timeout.*"