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To set the responsive font size, use the ‘viewport width’ and set it to ‘vw’ unit. You can try to run the following code to use ‘vw’ unit −ExampleLive Demo h1 { font-size:8vw; } This is demo heading This is demo text.
Use the CSS :hover selector to style links on mouse over with CSS. You can try to run the following code to implement the :hover selector −ExampleLive Demo a:hover { background-color: orange; } Qries Keep the mouse cursor on the above link and see the effect.
To change the root username in MySQL, you need to use UPDATE and SET command. The syntax is as follows −UPDATE user set user = ’yourNewUserName’ WHERE user = ’root’;To understand the above syntax, let us switch the database to MySQL using USE command.The query is as follows to switch the database.mysql> use mysql; Database changedNow list all the users from MySQL.user table. The query is as follows −mysql> select user from MySQL.user;The following is the output −+------------------+ | user | +------------------+ | Manish | | User2 ... Read More
To select the element that has focus, use the: focus selector. You can try to run the following code to implement the: focus selector −Example input:focus { background-color: green; } Subject Student: Age:
MongoDB insertOne() inserts a document into a collection, whereas updateOne() update a single document in a collection based on a query filter.Let us create a collection with documents −> db.demo735.insertOne({id:1, Name:"Chris"}); { "acknowledged" : true, "insertedId" : ObjectId("5ead51b657bb72a10bcf0652") } > db.demo735.insertOne({id:1, Name:"David"}); { "acknowledged" : true, "insertedId" : ObjectId("5ead51bb57bb72a10bcf0653") } > db.demo735.insertOne({id:1, Name:"Bob"}); { "acknowledged" : true, "insertedId" : ObjectId("5ead51be57bb72a10bcf0654") } > db.demo735.insertOne({id:1, Name:"Carol"}); { "acknowledged" : true, "insertedId" : ObjectId("5ead51c757bb72a10bcf0655") }Display all documents from a collection with the help of find() method −> db.demo735.find();This will produce the following output −{ "_id" ... Read More
Use the :focus selector to select the element that has focus. You can try to run the following code to implement the :focus selectorExample input:focus { background-color: green; } Subject Student: Age:
You can use DISTINCT with RLIKE operator to find a list of city names that do not start with vowels.The syntax is as follows −SELECT DISTINCT yourCityColumnName FROM yourTableName WHERE yourCityColumnName NOT RLIKE ‘ ^[AEIOUaeiou].*$’;To understand the above syntax, let us create a table. Here, we have a column for city names.The query to create a table is as follows −mysql> create table Employee_Information -> ( -> Id int NOT NULL AUTO_INCREMENT, -> EmployeeName varchar(20), -> CityName varchar(20), -> PRIMARY KEY(Id) -> ); Query OK, 0 rows affected (0.76 sec)Insert some records in the ... Read More
To get the difference between dates in MongpDB, use aggregate(). Let us create a collection with documents −> db.demo734.insertOne({GivenDate:new ISODate("2020-01-10")}); { "acknowledged" : true, "insertedId" : ObjectId("5ead4f1a57bb72a10bcf064e") } > db.demo734.insertOne({GivenDate:new ISODate("2020-02-20")}); { "acknowledged" : true, "insertedId" : ObjectId("5ead4f2157bb72a10bcf064f") } > db.demo734.insertOne({GivenDate:new ISODate("2010-12-01")}); { "acknowledged" : true, "insertedId" : ObjectId("5ead4f2b57bb72a10bcf0650") } > db.demo734.insertOne({GivenDate:new ISODate("2020-05-01")}); { "acknowledged" : true, "insertedId" : ObjectId("5ead506f57bb72a10bcf0651") }Display all documents from a collection with the help of find() method −> db.demo734.find();This will produce the following output −{ "_id" : ObjectId("5ead4f1a57bb72a10bcf064e"), "GivenDate" : ISODate("2020-01-10T00:00:00Z") } { "_id" : ObjectId("5ead4f2157bb72a10bcf064f"), "GivenDate" ... Read More
To remove all characters after the last comma in the string, you can use SUBSTRING_INDEX().If you do not know the location of the last comma, then you need to find the last comma dynamically using LENGTH().The syntax is as follows −UPDATE yourTableName set yourColumnName = SUBSTRING_INDEX(yourColumnName, ', ', LENGTH(yourColumnName) - LENGTH(REPLACE(yourColumnName, ', ', '')));To understand the above syntax, let us create a table. The query to create a table is as follows −mysql> create table RemoveAllCharacters -> ( -> Id int NOT NULL AUTO_INCREMENT, -> FullInfo varchar(200), -> PRIMARY KEY(Id) -> ); Query OK, 0 ... Read More