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Smita Kapse has Published 498 Articles
Smita Kapse
195 Views
Yes, for this, use $indexOfCP operator along with aggregate framework. Let us first create a collection with documents −> db.patterDemo.insertOne( { "ClientName": "John", "ClientWebsiteName":"webbuziness.com/John/business" } ); { "acknowledged" : true, "insertedId" : ObjectId("5cea40acef71edecf6a1f68d") } > db.patterDemo.insertOne( { "ClientName": "Carol", ... Read More
Smita Kapse
128 Views
The DROP TABLE removes the table completely and also removes all data. If you want to remove all data completely and wants the table structure, then you can use TRUNCATE TABLE command. The TRUNCATE command will recreate the table.Let us first check the DROP TABLE. For that, we will first ... Read More
Smita Kapse
313 Views
To retrieve an embedded object as a document, use the aggregation $replaceRoot. Let us first create a collection with documents −> db.embeddedObjectDemo.insertOne( { _id: new ObjectId(), "UserDetails": { "UserName": "John", "UserAge": 24, "UserEmailId": "John22@gmail.com" } } ); { "acknowledged" : true, "insertedId" : ... Read More
Smita Kapse
636 Views
To extract the particular element in MongoDB, you can use $elemMatch operator. Let us first create a collection with documents −> db.particularElementDemo.insertOne( { "GroupId" :"Group-1", "UserDetails" : [ { "UserName" : "John", ... Read More
Smita Kapse
235 Views
You can use ORDER BY for this. Let us first create a table −mysql> create table DemoTable ( Value int ); Query OK, 0 rows affected (0.20 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values(20); Query OK, 1 row affected (0.07 ... Read More
Smita Kapse
210 Views
Use $addToSet operator to ensures that there are no duplicate items added to the set. Let us first create a collection with documents −> db.getDistinctDemo.insertOne({"Values":[100, 200]}); { "acknowledged" : true, "insertedId" : ObjectId("5cef69f9ef71edecf6a1f69d") } > db.getDistinctDemo.insertOne({"Values":[300, 100]}); { "acknowledged" : true, "insertedId" : ObjectId("5cef6a07ef71edecf6a1f69e") }Display all ... Read More
Smita Kapse
179 Views
You can use ORDER BY RIGHT() for this. Let us first create a table −mysql> create table DemoTable ( UserId varchar(100) ); Query OK, 0 rows affected (0.33 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('User1234'); Query OK, 1 row affected ... Read More
Smita Kapse
203 Views
Let us first create a collection with documents −> db.queryMongoValueDemo.insertOne( { _id:101, "ScoreDetails":[{Score:80}, {Score:45}, {Score:25}, {Score:70}] } ); { "acknowledged" : true, "insertedId" : 101 } > db.queryMongoValueDemo.insertOne( { _id:102, "ScoreDetails":[{Score:80}, {Score:24}, {Score:34}] } ... Read More
Smita Kapse
72 Views
The getMaxColumnsInGroupBy() method of the DatabaseMetaData interface is used to find out the maximum number of columns that the underlying database allows in a GROUP BY clause.This method returns an integer value, representing the maximum number of columns allowed in a GROUP BY clause. If this value is 0 it ... Read More
Smita Kapse
784 Views
You can use GROUP_CONCAT() function from MySQL to display result as a comma separated list. Let us first create a table −mysql> create table DemoTable ( Value int ); Query OK, 0 rows affected (0.26 sec)Insert some records in the table using insert command −mysql> insert into ... Read More