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JSON5 Condition Expressions ​

Used by <query where="..."> and <when test="...">.

Instead of SQL-like strings, use JSON5 objects to describe filtering and branching conditions.

Supported Operators ​

Only these 10 operators are supported:

$and, $or, $eq, $ne, $gt, $gte, $lt, $lte, $contains, $startswith

Basic Forms ​

Field shorthand, equivalent to $eq:

json5
{ status: 'published' }

Explicit operator:

json5
{ age: { $gte: 18 } }

Combined form:

json5
{
  $and: [
    { status: { $eq: 'published' } },
    { title: { $contains: keyword } }
  ]
}

Operator Reference ​

OperatorMeaningExample
$eqEquals{ id: { $eq: '123' } }
$neNot equal{ status: { $ne: 'deleted' } }
$gtGreater than{ score: { $gt: 90 } }
$gteGreater than or equal{ price: { $gte: 100 } }
$ltLess than{ stock: { $lt: 10 } }
$lteLess than or equal{ level: { $lte: 3 } }
$containsContains, often for strings{ title: { $contains: 'hello' } }
$startswithPrefix match{ code: { $startswith: 'SKU-' } }
$andAll conditions must match{ $and: [ {...}, {...} ] }
$orAny condition may match{ $or: [ {...}, {...} ] }

Conditions can reference variables defined by <let>, such as keyword or min_age.

Using Conditions in query ​

A fixed equality condition:

html
<k-data>
    <query
        as="articles"
        source="content"
        resource="article"
        action="list"
        where="{title:'News'}"
        export
    ></query>
</k-data>

A condition can also reference a URL parameter defined by <let>:

html
<k-data>
    <let as="keyword" source="queryString" from="keyword" default="''" />
    <query
        as="articles"
        source="content"
        resource="article"
        action="list"
        where="{title:{$contains:keyword}}"
        export
    ></query>
</k-data>

Use $and or $or to combine multiple conditions:

json5
{
  $and: [
    { status: 'published' },
    { title: { $contains: keyword } }
  ]
}

Using Conditions in when ​

html
<k-data>
    <let as="status" source="queryString" from="status" default="'draft'" />
    <when test="{status:'published'}">
        <let as="message" default="'Published'" export />
        <else>
            <let as="message" default="'Not published'" export />
        </else>
    </when>
</k-data>