Filter operators for collections (Java)
Many Data API commands, like Find documents (Java), accept a filter parameter to determine which documents to return or update. The filter parameter uses one or more filter operators.
You must use & to escape any . or & in field names in a filter.
Dot notation, which is used to reference nested fields, should not be escaped.
For more information, see Work with . and & in field names (Java).
Operators
You can use the following operators in a filter. All operators are case-sensitive.
Equal (default)
The $eq operator matches documents where the specified field is equal to the specified value.
This is the default when you do not specify an operator.
import com.datastax.astra.client.DataAPIClients;
import com.datastax.astra.client.collections.Collection;
import com.datastax.astra.client.collections.definition.documents.Document;
import com.datastax.astra.client.core.query.Filter;
import com.datastax.astra.client.core.query.Filters;
import java.util.Optional;
public class Example {
public static void main(String[] args) {
// Get an existing collection
Collection<Document> collection =
DataAPIClients.clientHCD("USERNAME", "PASSWORD")
.getDatabase("API_ENDPOINT", "KEYSPACE_NAME")
.getCollection("COLLECTION_NAME");
// Find a document
Filter filter = Filters.eq("number_of_pages", 714);
Optional<Document> result = collection.findOne(filter);
System.out.println(result);
}
}
Not equal
The $ne operator matches documents where the specified field is not equal to the specified value.
import com.datastax.astra.client.DataAPIClients;
import com.datastax.astra.client.collections.Collection;
import com.datastax.astra.client.collections.definition.documents.Document;
import com.datastax.astra.client.core.query.Filter;
import com.datastax.astra.client.core.query.Filters;
import java.util.Optional;
public class Example {
public static void main(String[] args) {
// Get an existing collection
Collection<Document> collection =
DataAPIClients.clientHCD("USERNAME", "PASSWORD")
.getDatabase("API_ENDPOINT", "KEYSPACE_NAME")
.getCollection("COLLECTION_NAME");
// Find a document
Filter filter = Filters.ne("number_of_pages", 300);
Optional<Document> result = collection.findOne(filter);
System.out.println(result);
}
}
Greater than
The $gt operator matches documents where the specified field is greater than the specified value.
import com.datastax.astra.client.DataAPIClients;
import com.datastax.astra.client.collections.Collection;
import com.datastax.astra.client.collections.definition.documents.Document;
import com.datastax.astra.client.core.query.Filter;
import com.datastax.astra.client.core.query.Filters;
import java.util.Optional;
public class Example {
public static void main(String[] args) {
// Get an existing collection
Collection<Document> collection =
DataAPIClients.clientHCD("USERNAME", "PASSWORD")
.getDatabase("API_ENDPOINT", "KEYSPACE_NAME")
.getCollection("COLLECTION_NAME");
// Find a document
Filter filter = Filters.gt("number_of_pages", 300);
Optional<Document> result = collection.findOne(filter);
System.out.println(result);
}
}
Greater than or equal
The $gte operator matches documents where the specified field is greater than or equal to the specified value.
import com.datastax.astra.client.DataAPIClients;
import com.datastax.astra.client.collections.Collection;
import com.datastax.astra.client.collections.definition.documents.Document;
import com.datastax.astra.client.core.query.Filter;
import com.datastax.astra.client.core.query.Filters;
import java.util.Optional;
public class Example {
public static void main(String[] args) {
// Get an existing collection
Collection<Document> collection =
DataAPIClients.clientHCD("USERNAME", "PASSWORD")
.getDatabase("API_ENDPOINT", "KEYSPACE_NAME")
.getCollection("COLLECTION_NAME");
// Find a document
Filter filter = Filters.gte("number_of_pages", 300);
Optional<Document> result = collection.findOne(filter);
System.out.println(result);
}
}
Less than
The $lt operator matches documents where the specified field is less than the specified value.
import com.datastax.astra.client.DataAPIClients;
import com.datastax.astra.client.collections.Collection;
import com.datastax.astra.client.collections.definition.documents.Document;
import com.datastax.astra.client.core.query.Filter;
import com.datastax.astra.client.core.query.Filters;
import java.util.Optional;
public class Example {
public static void main(String[] args) {
// Get an existing collection
Collection<Document> collection =
DataAPIClients.clientHCD("USERNAME", "PASSWORD")
.getDatabase("API_ENDPOINT", "KEYSPACE_NAME")
.getCollection("COLLECTION_NAME");
// Find a document
Filter filter = Filters.lt("number_of_pages", 300);
Optional<Document> result = collection.findOne(filter);
System.out.println(result);
}
}
Less than or equal
The $lte operator matches documents where the specified field is less than or equal to the specified value.
import com.datastax.astra.client.DataAPIClients;
import com.datastax.astra.client.collections.Collection;
import com.datastax.astra.client.collections.definition.documents.Document;
import com.datastax.astra.client.core.query.Filter;
import com.datastax.astra.client.core.query.Filters;
import java.util.Optional;
public class Example {
public static void main(String[] args) {
// Get an existing collection
Collection<Document> collection =
DataAPIClients.clientHCD("USERNAME", "PASSWORD")
.getDatabase("API_ENDPOINT", "KEYSPACE_NAME")
.getCollection("COLLECTION_NAME");
// Find a document
Filter filter = Filters.lte("number_of_pages", 300);
Optional<Document> result = collection.findOne(filter);
System.out.println(result);
}
}
In
The $in operator matches documents where the field contains any of the specified values.
For fields that store an array, the operator matches documents where the array contains any of the specified values.
import com.datastax.astra.client.DataAPIClients;
import com.datastax.astra.client.collections.Collection;
import com.datastax.astra.client.collections.definition.documents.Document;
import com.datastax.astra.client.core.query.Filter;
import com.datastax.astra.client.core.query.Filters;
import java.util.Optional;
public class Example {
public static void main(String[] args) {
// Get an existing collection
Collection<Document> collection =
DataAPIClients.clientHCD("USERNAME", "PASSWORD")
.getDatabase("API_ENDPOINT", "KEYSPACE_NAME")
.getCollection("COLLECTION_NAME");
// Find a document
Filter filter = Filters.in("genres", "Fantasy", "Romance");
Optional<Document> result = collection.findOne(filter);
System.out.println(result);
}
}
If you have only one value to match, you can use the single value instead of an array, like { "$in": "VALUE" }.
Not in
The $nin operator matches documents where the field doesn’t contain any of the specified values.
import com.datastax.astra.client.DataAPIClients;
import com.datastax.astra.client.collections.Collection;
import com.datastax.astra.client.collections.definition.documents.Document;
import com.datastax.astra.client.core.query.Filter;
import com.datastax.astra.client.core.query.Filters;
import java.util.Optional;
public class Example {
public static void main(String[] args) {
// Get an existing collection
Collection<Document> collection =
DataAPIClients.clientHCD("USERNAME", "PASSWORD")
.getDatabase("API_ENDPOINT", "KEYSPACE_NAME")
.getCollection("COLLECTION_NAME");
// Find a document
Filter filter = Filters.nin("genres", "Fantasy", "Romance");
Optional<Document> result = collection.findOne(filter);
System.out.println(result);
}
}
Exists
The $exists operator matches documents that have the specified field, even if the field value is null.
import com.datastax.astra.client.DataAPIClients;
import com.datastax.astra.client.collections.Collection;
import com.datastax.astra.client.collections.definition.documents.Document;
import com.datastax.astra.client.core.query.Filter;
import com.datastax.astra.client.core.query.Filters;
import java.util.Optional;
public class Example {
public static void main(String[] args) {
// Get an existing collection
Collection<Document> collection =
DataAPIClients.clientHCD("USERNAME", "PASSWORD")
.getDatabase("API_ENDPOINT", "KEYSPACE_NAME")
.getCollection("COLLECTION_NAME");
// Find a document
Filter filter = Filters.exists("borrower");
Optional<Document> result = collection.findOne(filter);
System.out.println(result);
}
}
All
For fields that store an array, the $all operator matches documents where the array contains all of the specified values.
import com.datastax.astra.client.DataAPIClients;
import com.datastax.astra.client.collections.Collection;
import com.datastax.astra.client.collections.definition.documents.Document;
import com.datastax.astra.client.core.query.Filter;
import com.datastax.astra.client.core.query.Filters;
import java.util.Optional;
public class Example {
public static void main(String[] args) {
// Get an existing collection
Collection<Document> collection =
DataAPIClients.clientHCD("USERNAME", "PASSWORD")
.getDatabase("API_ENDPOINT", "KEYSPACE_NAME")
.getCollection("COLLECTION_NAME");
// Find a document
Filter filter = Filters.all("genres", "Fantasy", "Romance");
Optional<Document> result = collection.findOne(filter);
System.out.println(result);
}
}
Size
For fields that store an array, the $size operator matches documents where the array has the specified number of elements.
import com.datastax.astra.client.DataAPIClients;
import com.datastax.astra.client.collections.Collection;
import com.datastax.astra.client.collections.definition.documents.Document;
import com.datastax.astra.client.core.query.Filter;
import com.datastax.astra.client.core.query.Filters;
import java.util.Optional;
public class Example {
public static void main(String[] args) {
// Get an existing collection
Collection<Document> collection =
DataAPIClients.clientHCD("USERNAME", "PASSWORD")
.getDatabase("API_ENDPOINT", "KEYSPACE_NAME")
.getCollection("COLLECTION_NAME");
// Find a document
Filter filter = Filters.hasSize("genres", 3);
Optional<Document> result = collection.findOne(filter);
System.out.println(result);
}
}
Not
The $not operator returns documents that don’t match the condition of the clause.
import com.datastax.astra.client.DataAPIClients;
import com.datastax.astra.client.collections.Collection;
import com.datastax.astra.client.collections.definition.documents.Document;
import com.datastax.astra.client.core.query.Filter;
import com.datastax.astra.client.core.query.Filters;
import java.util.Optional;
public class Example {
public static void main(String[] args) {
// Get an existing collection
Collection<Document> collection =
DataAPIClients.clientHCD("USERNAME", "PASSWORD")
.getDatabase("API_ENDPOINT", "KEYSPACE_NAME")
.getCollection("COLLECTION_NAME");
// Find a document
Filter filter = Filters.not(Filters.eq("is_checked_out", false));
Optional<Document> result = collection.findOne(filter);
System.out.println(result);
}
}
Combine operators (And, Or)
The $and operator joins clauses with a logical AND.
Only documents that match the conditions of all clauses are returned.
The $or operator joins clauses with a logical OR.
Documents that match the condition of any of the clauses are returned.
You can use $and and $or separately or together.
If you want to match multiple flexible conditions, use $and and $or together in the same filter:
import com.datastax.astra.client.DataAPIClients;
import com.datastax.astra.client.collections.Collection;
import com.datastax.astra.client.collections.definition.documents.Document;
import com.datastax.astra.client.core.query.Filter;
import com.datastax.astra.client.core.query.Filters;
import java.util.Optional;
public class Example {
public static void main(String[] args) {
// Get an existing collection
Collection<Document> collection =
DataAPIClients.clientHCD("USERNAME", "PASSWORD")
.getDatabase("API_ENDPOINT", "KEYSPACE_NAME")
.getCollection("COLLECTION_NAME");
// Find a document
Filter filter =
Filters.and(
Filters.or(Filters.eq("is_checked_out", false), Filters.lt("number_of_pages", 300)),
Filters.or(
Filters.in("genres", "Fantasy", "Romance"), Filters.gte("publication_year", 2002)));
Optional<Document> result = collection.findOne(filter);
System.out.println(result);
}
}
To filter on a range of values, use $and with $lt/$lte and $gt/$gte:
import com.datastax.astra.client.DataAPIClients;
import com.datastax.astra.client.collections.Collection;
import com.datastax.astra.client.collections.definition.documents.Document;
import com.datastax.astra.client.core.query.Filter;
import com.datastax.astra.client.core.query.Filters;
import java.util.Optional;
public class Example {
public static void main(String[] args) {
// Get an existing collection
Collection<Document> collection =
DataAPIClients.clientHCD("USERNAME", "PASSWORD")
.getDatabase("API_ENDPOINT", "KEYSPACE_NAME")
.getCollection("COLLECTION_NAME");
// Find a document
Filter filter =
Filters.and(Filters.lt("number_of_pages", 300), Filters.gte("number_of_pages", 200));
Optional<Document> result = collection.findOne(filter);
System.out.println(result);
}
}
Filter nested fields
Use dot notation to filter nested fields.
For example, field.subfield.subsubfield.
import com.datastax.astra.client.DataAPIClients;
import com.datastax.astra.client.collections.Collection;
import com.datastax.astra.client.collections.definition.documents.Document;
import com.datastax.astra.client.core.query.Filter;
import com.datastax.astra.client.core.query.Filters;
import java.util.Optional;
public class Example {
public static void main(String[] args) {
// Get an existing collection
Collection<Document> collection =
DataAPIClients.clientHCD("USERNAME", "PASSWORD")
.getDatabase("API_ENDPOINT", "KEYSPACE_NAME")
.getCollection("COLLECTION_NAME");
// Find a document
Filter filter = Filters.eq("metadata.language", "French");
Optional<Document> result = collection.findOne(filter);
System.out.println(result);
}
}