OData Query Syntax¶

FC Selector uses OData v4 query syntax. This page covers all supported operators and functions.

Query Parameters¶

Parameter	Description	Example
`$filter`	Filter results	`$filter=status eq 'published'`
`$select`	Select specific fields	`$select=id,title,author`
`$expand`	Include related entities	`$expand=author,categories`
`$orderby`	Sort results	`$orderby=created_at desc`
`$top`	Limit results	`$top=10`
`$skip`	Skip results	`$skip=20`
`$count`	Include total count	`$count=true`

$filter¶

Comparison Operators¶

Operator	Description	Example
`eq`	Equal	`status eq 'published'`
`ne`	Not equal	`status ne 'draft'`
`gt`	Greater than	`rating gt 4.0`
`ge`	Greater than or equal	`rating ge 4.0`
`lt`	Less than	`price lt 100`
`le`	Less than or equal	`price le 100`

# Examples
$filter=status eq 'published'
$filter=rating gt 4.0
$filter=created_at ge 2024-01-01

Logical Operators¶

Operator	Description	Example
`and`	Logical AND	`status eq 'published' and featured eq true`
`or`	Logical OR	`status eq 'draft' or status eq 'review'`
`not`	Logical NOT	`not featured`

# Combined filters
$filter=status eq 'published' and rating gt 4.0
$filter=status eq 'published' and (featured eq true or rating gt 4.5)
$filter=not (status eq 'draft')

String Functions¶

Function	Description	Example
`contains`	Contains substring	`contains(title, 'Python')`
`startswith`	Starts with	`startswith(title, 'How')`
`endswith`	Ends with	`endswith(email, '@example.com')`
`tolower`	Convert to lowercase	`tolower(title) eq 'hello'`
`toupper`	Convert to uppercase	`toupper(status) eq 'PUBLISHED'`

# String function examples
$filter=contains(title, 'Django')
$filter=startswith(title, 'Getting Started')
$filter=tolower(status) eq 'published'

Null Checks¶

$filter=published_at eq null
$filter=published_at ne null

Boolean Fields¶

$filter=featured eq true
$filter=is_active eq false
$filter=featured  # Shorthand for featured eq true

Date/Time¶

$filter=created_at gt 2024-01-01
$filter=created_at ge 2024-01-01T00:00:00Z
$filter=created_at lt 2024-12-31

Nested Properties¶

Access related entity properties with /:

$filter=author/name eq 'John'
$filter=author/email eq 'john@example.com'
$filter=author/profile/bio ne null

Collection Operators¶

For ManyToMany and reverse ForeignKey relations:

# Any: at least one item matches
$filter=categories/any(c: c/name eq 'Python')
$filter=tags/any(t: contains(t/name, 'tutorial'))

# All: all items match
$filter=comments/all(c: c/approved eq true)

$select¶

Choose which fields to return:

$select=id,title,status
$select=id,title,author

Nested $select¶

Select fields from expanded relations:

$expand=author($select=name,email)
$expand=categories($select=id,name)

$expand¶

Include related entities:

# Single relation
$expand=author

# Multiple relations
$expand=author,categories

# Nested expand
$expand=author($expand=profile)

# With nested $select
$expand=author($select=name,email)

# Combined
$expand=author($select=name;$expand=profile($select=bio))

$orderby¶

Sort results:

# Ascending (default)
$orderby=title
$orderby=title asc

# Descending
$orderby=created_at desc

# Multiple fields
$orderby=featured desc,created_at desc

# Nested property
$orderby=author/name asc

$top and $skip¶

Pagination:

# First 10 results
$top=10

# Skip first 20, take next 10 (page 3)
$top=10&$skip=20

$count¶

Include total count in response:

$count=true

Complex Examples¶

Blog posts query¶

# Published posts with author, sorted by date, first 10
$filter=status eq 'published'&$select=id,title,excerpt,author&$expand=author($select=name)&$orderby=created_at desc&$top=10

Search with filters¶

# Posts containing "Django" in title, published, high rating
$filter=contains(title, 'Django') and status eq 'published' and rating gt 4.0&$orderby=rating desc

Nested relations¶

# Posts by specific author with categories
$filter=author/name eq 'John Doe'&$expand=author,categories&$select=id,title,author,categories

Pagination with count¶

# Page 3 (10 items per page) with total count
$top=10&$skip=20&$count=true

URL Encoding¶

Special characters must be URL-encoded:

Character	Encoded
Space	`%20` or `+`
`'`	`%27`
`"`	`%22`
`&`	`%26`

# Original
$filter=title eq 'Hello World'

# URL encoded
$filter=title%20eq%20%27Hello%20World%27

Most HTTP clients handle encoding automatically.