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MongoDB is a source-available, cross-platform, document-oriented database program. Classified as a NoSQL database product, MongoDB uses JSON -like documents with optional schemas . Released in February 2009 by 10gen (now MongoDB Inc. ), it supports features like sharding , replication , and ACID transactions (from version 4.0).
In order not to fill the data store with useless information, there is a policy to remove tombstones completely. For this, the system checks the age of the tombstone and removes it after a prescribed time has elapsed. In Apache Cassandra, this elapsed time is set with the GCGraceSeconds parameter [1] and the process is named Compaction. [2]
DELETE requires a shared table lock; Triggers fire; DELETE can be used in the case of: database link; DELETE returns the number of records deleted; Transaction log - DELETE needs to read records, check constraints, update block, update indexes, and generate redo / undo. All of this takes time, hence it takes time much longer than with TRUNCATE
A document-oriented database is a specialized key-value store, which itself is another NoSQL database category. In a simple key-value store, the document content is opaque. A document-oriented database provides APIs or a query/update language that exposes the ability to query or update based on the internal structure in the document. This ...
It supports facetting and percolating (a form of prospective search), [32] [33] which can be useful for notifying if new documents match for registered queries. Another feature, "gateway", handles the long-term persistence of the index; [34] for example, an index can be recovered from the gateway in the event of a server crash.
MongoDB Collections Documents Compatible with wire protocol version 6 and server version 3.6 of the MongoDB. [6] Gremlin Graphs Nodes and edges Compatible with version 3.2 of the Gremlin specification. Cassandra Table Row Compatible with version 4 of the Cassandra Query Language (CQL) wire protocol. Azure Table Storage Table Item etcd Key Value
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SQL was initially developed at IBM by Donald D. Chamberlin and Raymond F. Boyce after learning about the relational model from Edgar F. Codd [12] in the early 1970s. [13] This version, initially called SEQUEL (Structured English Query Language), was designed to manipulate and retrieve data stored in IBM's original quasirelational database management system, System R, which a group at IBM San ...