2.3.22 The NdbRecord Interface

This section provides information about the NdbRecord interface.

Decription

NdbRecord is an interface which provides a mapping to a full or a partial record stored in NDB. In the latter case, it can be used in conjunction with a bitmap to assist in access.

Parent

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Methods

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Types

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NdbRecord has no API methods of its own; rather, it acts as a handle that can be passed between various method calls for use in many different sorts of operations, including the following:

• Unique key reads and primary key reads

• Table scans and index scans

• DML operations involving unique keys or primary keys

• Operations involving index bounds

The same NdbRecord can be used simultaneously in multiple operations, transactions, and threads.

An NdbRecord can be created in NDB API programs by calling Dictionary::createRecord(). In addition, a number of NDB API methods have additional declarations that enable the programmer to leverage NdbRecord:

• NdbScanOperation::nextResult()

• NdbScanOperation::lockCurrentTuple()

• NdbScanOperation::updateCurrentTuple()

• NdbScanOperation::deleteCurrentTuple()

• Dictionary::createRecord()

• Dictionary::releaseRecord()

• NdbTransaction::readTuple()

• NdbTransaction::insertTuple()

• NdbTransaction::updateTuple()

• NdbTransaction::writeTuple()

• NdbTransaction::deleteTuple()

• NdbTransaction::scanTable()

• NdbTransaction::scanIndex()

The following members of NdbIndexScanOperation and NdbDictionary can also be used with NdbRecord scans:

• IndexBound is a structure used to describe index scan bounds.

• RecordSpecification is a structure used to specify columns and range offsets.

You can also use NdbRecord in conjunction with the PartitionSpec structure to perform scans that take advantage of partition pruning, using NdbIndexScanOperation::setBound().