Filter Conditions (Reference)

A filter condition can be used either on its own, as a filter specification, or at a lower level, in the query clause of a composite filter specification.

A filter condition is a JSON object whose members form one or more of these clauses:

• scalar-equality clause

• field-condition clause

• logical combining clause

• nested-condition clause

• ID clause

• text-contains clause

• special-criterion clause

A filter condition is true if and only if all of its clauses are true. A filter condition can be empty (the empty object, {}), in which case all of its (zero) clauses are vacuously true (the filter condition is satisfied).

For example, if a filter involves only one filter condition and it is empty then all documents of the collection are selected. In this case, a find operation returns all of the documents, and a remove operation removes them all.

• Scalar-Equality Clause (Reference)

  A scalar-equality clause tests whether a given object field is equal to a given scalar value.

• Field-Condition Clause (Reference)

  A field-condition clause specifies that a given object field must satisfy a given set of criteria. It constrains a field using one or more condition-operator clauses, each of which is a comparison clause, a not clause, or an item-method clause.

• Logical Combining Clause (Reference)

  A logical combining clause combines the effects of multiple non-empty filter conditions.

• Nested-Condition Clause (Reference)

  You use a nested-condition clause to apply multiple conditions at the same time, to array elements that are objects.

• ID Clause (Reference)

  Other filter operators generally look for particular JSON fields within the content of documents and try to match their values. An ID clause, which uses operator $id, instead matches document keys. It thus matches document metadata, not document content.

• Text-Contains Clause (Reference)

  A text-contains clause is operator $textContains with a string value that is used as a full-text search pattern: $textcontains:pattern. It matches a non-JSON document only if some text in the document matches that pattern. Matching is Oracle Text full-text matching.

• Special-Criterion Clause (Reference)

  A special criterion clause is a spatial clause (with operator $near, $intersects, or $within), or a contains clause (with operator $contains).