Writing where clauses
To update or remove all items that match a given criteria, you may have to write more complex queries than simple comparisons for equality. For that, use query operators.
Using query operators
The following query operators are available that match simple types:
| Operator | Description |
|---|---|
$greaterThan |
Matches fields greater than the given value. |
$greaterThanOrEqualTo |
Matches fields greater than or equal to the given value. |
$lessThan |
Matches fields less than the given value. |
$lessThanOrEqualTo |
Matches fields less than or equal to the given value. |
$notEqualTo |
Matches fields not equal to the given value. |
E.g., to remove all invoices that have an amount less than 1000, use the following code:
invoices.remove({
where: { amount: { $lessThan: 1000 }}
});
The following query operators are available that match arrays:
| Operator | Description |
|---|---|
$contains |
Matches arrays that contain the given value. |
$doesNotContain |
Matches arrays that do not contain the given value. |
E.g., to remove all invoices that are tagged with the private tag, use the following code:
invoices.remove({
where: { tags: { $contains: 'private' }}
});
Using logical operators
To combine multiple where clauses, use logical operators. The following logical operators are available:
| Operator | Description |
|---|---|
$and |
Matches items that match all conditions. |
$or |
Matches items that match at least one condition. |
E.g., to remove all invoices that have an amount less than 1000 or are tagged with the private tag, use the following code:
invoices.remove({
where: {
$or: [
{ amount: { $lessThan: 1000 }},
{ tags: { $contains: 'private' }}
]
}
});