org.apache.flink.connector.mongodb.common.utils

Class MongoValidationUtils

java.lang.Object

org.apache.flink.connector.mongodb.common.utils.MongoValidationUtils

@Internal
public class MongoValidationUtils
extends Object

Utility methods for validating MongoDB properties.

Field Summary

Fields

Modifier and Type	Field and Description
static Set<org.apache.flink.table.types.logical.LogicalTypeRoot>	ALLOWED_PRIMARY_KEY_TYPES

Method Summary

Modifier and Type	Method and Description
static void	validatePrimaryKey(org.apache.flink.table.types.DataType primaryKeyDataType) Checks that the table does not have a primary key defined on illegal types.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

ALLOWED_PRIMARY_KEY_TYPES

public static final Set<org.apache.flink.table.types.logical.LogicalTypeRoot> ALLOWED_PRIMARY_KEY_TYPES

Method Detail

validatePrimaryKey

public static void validatePrimaryKey(org.apache.flink.table.types.DataType primaryKeyDataType)

Checks that the table does not have a primary key defined on illegal types. In MongoDB the primary key is used to calculate the MongoDB document _id, which may be of any BsonType other than a BsonType.ARRAY. Its value must be unique and immutable in the collection.

MongoDB creates a unique index on the _id field during the creation of a collection. There are also some constraints on the primary key index. For more detailed introduction, you can refer to Index Key Limit.

• Before MongoDB 4.2, the total size of an index entry, which can include structural overhead depending on the BSON type, must be less than 1024 bytes.
• Starting in version 4.2, MongoDB removes the Index Key Limit.

As of now it is extracted by MongoPrimaryKeyExtractor according to the primary key specified by the Flink table schema.

• When there's only a single field in the specified primary key, we convert the field data to bson value as _id of the corresponding document.
• When there's multiple fields in the specified primary key, we convert and composite these fields into a BsonType.DOCUMENT as the _id of the corresponding document. For example, if have a primary key statement PRIMARY KEY (f1, f2) NOT ENFORCED , the extracted _id will be the form like _id: {f1: v1, f2: v2}

The illegal types are mostly LogicalTypeFamily.COLLECTION types and LogicalTypeRoot.RAW type and other types that cannot be converted to BsonType by RowDataToBsonConverters.