MongoDB is one of the most popular NoSQL databases that use documents in its arrangement, while Oracle is a relational database management system that uses Structured Query Language to maintain data. Both MongoDB and Oracle can be installed and used on all major Operating systems such as Windows, Linux, Unix, etc. An Oracle database is known for databases, tables, and data, whereas a MongoDB is composed of documents in the fields. This article will explain the technical difference between MongoDB and Oracle.
MongoDB is a grouping of MongoDB documents. In oracle, data is stored in the table while a collection is the equivalent of an RDBMS table. A collection is included in a single database. Collections do not use a schema.
>use test switched to db test >db.createCollection("myfirstcollection") { "ok" : 1 } >
CREATE TABLE employee( emp_id NUMBER GENERATED BY DEFAULT AS IDENTITY, empname VARCHAR2(60) NOT NULL, address VARCHAR2(60) NOT NULL, PRIMARY KEY(emp_id) );
In the Oracle database, the GROUP BY clause can be used to group rows by using the values of columns. This clause is one of the most widely used clauses in analytical SQL queries. It returns one row per group and it is used with various aggregate functions like AVG(), MAX(), MIN(), SUM(), and COUNT(). In MongoDB, Aggregations operations use data records and give calculated or computed output. It is used to group values from various documents collectively and can deliver various methods on the distributed data to pass a single output. The Oracle’s count(*) and the group by are an equivalent of MongoDB aggregation.
SELECT first_id, COUNT(*) AS total_rows, SUM(sales) AS sales_amount FROM product_sales GROUP BY first_id ORDER BY first_id;
> db.testcol.aggregate([{$group : {_id : "$new_employee", emp_value : {$sum : 1}}}]) { "_id" : "employee", "emp_value" : 2 } { "_id" : "113a", "emp_value" : 1 } >
The Regular expression in the Oracle database can be used with a collection of Oracle SQL functions that enable users to search and handle string data. Regular expressions are an important part of any programming language. In the Oracle database, regular expressions can use various functions in any environment where Oracle Database SQL is used.
Regular Expressions are often utilized in all programming languages. Their job is to hunt for a pattern or word in any string. MongoDB also implements the use of the regular expression for string matching. For this, it uses the $regex operator. MongoDB applies the Perl Compatible Regular Expression as its regular expression language.
> db.posts.find({post_text:{$regex:"employee"}}).pretty() { "_id" : ObjectId("6cc7dr48f1cc4467e2163ft0"), "post_text" : "Best employee", "tags" : [ "employee", "best" ] }
The update command or method is present in both relational and non-relational databases. MongoDB uses update() and save() methods to update or manipulate the document into a collection. The update() method modifies the values in the current document and the save() method substitutes the current document with the document declared in save() method. In the Oracle database, the update command is used to update or modify the data from the table. The update command is a part of data manipulation languages. The update method() in MongoDB updates the value present in the document.
>db.testcol.update({'title':'Physics'},{$set:{'title':'New Physics Topic'}}) WriteResult({ "nMatched" : 2, "nUpserted" : 1, "nModified" : 1 })
UPDATE employee ee SET (ee.id, ee.address) = (SELECT dd.id, dd.address FROM dept dd WHERE dd.id = ee.id) WHERE EXISTS (SELECT 1 FROM dept WHERE id = ee.id);
To take a backup of the database in MongoDB, the mongodump command can be used. This command is used to dump the whole data of the server into the dump directory. This mongodump command can also be used with various options. In Oracle, the database backup utility is responsible for the backup and restore of the database. Oracle presents the backup utility by giving UI as well as common options.
>mongodump
RUN { ALLOCATE CHANNEL ch15 TYPE DISK MAXPIECESIZE 12G; BACKUP FORMAT '/u01/app/oracle/BACKUP/%d_C_%D_%u_s%s_p%p' DATABASE CURRENT CONTROLFILE FORMAT '/u01/app/oracle/BACKUP/%d_D_%T_%u' SPFILE FORMAT '/u01/app/oracle/BACKUP/%d_C_%T_%u' PLUS ARCHIVELOG FORMAT '/u01/app/oracle/BACKUP/%d_D_%T_%u_s%s_p%p'; RELEASE CHANNEL ch15; }
The drop command in MongoDb is used to drop the database and the related indexes completely. This command is one of the most important MongoDB commands as it is responsible for the overall performance and scalability of the database. In the Oracle database, the drop command is used to delete the table from the database or database from the schema. This command is a part of the dynamic definition languages and is used to drop columns from the table too.
>use testdb switched to db testdb >db.dropDatabase() >{ "dropped" : "testdb", "ok" : 1 } >
An index in MongoDB is a specific data structure that contains the data of fields of documents on which the index is built. Indexes increase the activity of search services in the database.
In Oracle and MongoDB, Indexes are responsible for speeding up the search query by giving fast access. Indexes in the relational database management system or non-relational database management system are not always relevant. Indexes are great at reducing the time it requires to search and obtain data using the SELECT statements.
Sometimes index can really decrease the query performance to UPDATE, INSERT, or DELETE. In Oracle, the index is normally created to get the first or primary set of rows quickly when the table contains too much data in the table. This is responsible for the overall performance of the database.
>db.users.createIndex({"tags":1}) { "createdCollectionAutomatically" : false, "numIndexesBefore" : 5, "numIndexesAfter" : 6, "ok" : 1 } >
CREATE INDEX ix_test_10 ON employee (dno) TABLESPACE index_tbs;
In MongoDB, when the db.collection.find () utility is applied to hunt for documents in the collection, the event delivers a mark to the collection delivered which is named a cursor. In MongoDB, the cursor will be repeated implicitly when the output of the query is passed. But users can also explicitly search the objects reflected in the cursor one by one. The Cursor is a MongoDB Collection that is reflected in the find program performance. In simple words when users request a find method, all the records which are delivered are stored in an implicit cursor. If a find method accounts for a record then it indicates that the cursor has a 0 – 3 index.
In Oracle too, a cursor is one short or acting work area generated in the machine’s memory when a SQL statement is fired. A cursor holds data on a select statement and the lines of data obtained by it. There are two types of cursors in Oracle PL/SQL, implicit cursors and explicit cursors. This short work area is utilized to collect the data obtained from the database and manage this data. IT can contain more than one row but can treat only one row at a time. The collection of rows the cursor contains is described as the active set. Implicit cursors are created when INSERT, UPDATE and DELETE statements are fired by the user. On the other hand, explicit cursors are created when the user fires a SELECT statement that returns multiple rows. The cursor attributes in Oracle are %FOUND, %NOTFOUND, %ROWCOUNT, and %ISOPEN. Both implicit and explicit cursors work similarly but they vary in the process they are used.
The following example explains how this can be achieved.
var newEmp = db.Emp.find( { Empid : { $gt:5 }}); while(myEmp.hasNext()) { print(tojson(myEmp.next())); }
DECLARE l_a NUMBER := 1000; -- cursor CURSOR a_market IS SELECT * FROM market ORDER BY total DESC;
MongoDB gives many characteristics, such as authentication, entrance limitation, and encryption, to defend MongoDB. In MongoDB, authentication is the method of confirming the integrity of a client. When access control, i.e. permission, is allowed, MongoDB expects all clients to verify themselves to resolve their path. Although authentication and permission are almost related, authentication is different from permission. Authentication validates the integrity of a user; permission defines the authenticated user’s path to resources and services.
In Oracle, database security means establishing or revoking user movements on the database and other schema objects. Oracle is all about schemas and it uses schemas and security policies to maintain access to data. With the help of this, it can restrict the usage of various database resources. For example, Oracle can implement authentication on both the database level and the server level. It also supports various other things such as confirmation of the integrity of users and minimization of the uncertainty of illegal access. Oracle implements exceptional security benefits to defend business data security queries. In Oracle, database administrators can encrypt the data utilizing the Transparent Data Encryption (TDE) method. The security practices of Oracle make sure that only approved users can interpret the critical data in a database.
To secure your MongoDB implementation, MongoDB provides a variety of tools such as verification, security systems, and encryption. Some of the most significant security characteristics are:
The following are the features of the Oracle: