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Found 6705 Articles for Database

1K+ Views
Let us first create a tablemysql> create table recordsDemo -> ( -> UserId int, -> Value int -> ); Query OK, 0 rows affected (0.52 sec)Now insert some records in the table using insert command.The query is as followsmysql> insert into recordsDemo values(1, 10); Query OK, 1 row affected (0.17 sec) mysql> insert into recordsDemo values(3, 598); Query OK, 1 row affected (0.18 sec) mysql> insert into recordsDemo values(5, 786); Query OK, 1 row affected (0.25 sec) mysql> insert into recordsDemo values(7, 189); Query OK, 1 row affected (0.16 sec) mysql> insert into recordsDemo values(9, 345); ... Read More

255 Views
Let us see how to loop through a stored procedure in MySQLmysql> DELIMITER // mysql> CREATE PROCEDURE do_WhileDemo(LastValue INT) -> BEGIN -> SET @loop = 0; -> REPEAT -> SET @loop= @loop+ 1; -> select @loop; -> UNTIL @loop >LastValue -> END REPEAT; -> END // Query OK, 0 rows affected (0.17 sec) mysql> DELIMITER ;Now call the stored procedure with the help of CALL command.The query is as followsmysql> call do_WhileDemo(10);The following is the output+-------+ | ... Read More

160 Views
You need to use rand() function to select random result from MySQL.The syntax is as followsselect *from yourTableName order by rand() limit 1;To understand the above syntax, let us create a table. The query to create a table is as followsmysql> create table selectRandomRecord -> ( -> StudentId int NOT NULL AUTO_INCREMENT PRIMARY KEY, -> StudentName varchar(20) -> ); Query OK, 0 rows affected (0.53 sec)Insert some records in the table using insert command.The query is as followsmysql> insert into selectRandomRecord(StudentName) values('John'); Query OK, 1 row affected (0.17 sec) mysql> insert into selectRandomRecord(StudentName) values('Carol'); Query OK, ... Read More

101 Views
Both the getUsers() method and SHOW command can be used to list all users in the Mongo shell.Case 1 − Using getUsers()The syntax is as follows −db.getUsers();Case 2 − Using show commandThe syntax is as follows −show users;Let us implement both the syntaxes in order to list all users in the Mongo shell.Case 1 − The first query is as follows −> db.getUsers();The following is the output −[ { "_id" : "test.John", "user" : "John", "db" : "test", "roles" : [ { ... Read More

631 Views
In order to stop MongoDB in a single command, use the following syntax −mongo --eval "db.getSiblingDB('admin').shutdownServer()"Let us implement the above syntax in order to stop MongoDB in one command.First, use the shortcut key −Ctrl + C;The query is as follows −C:\Program Files\MongoDB\Server\4.0\bin>mongo --eval "db.getSiblingDB('admin').shutdownServer()"The following is the output − displaying the shutdown of the MongoDB server −MongoDB shell version v4.0.5 connecting to: mongodb://127.0.0.1:27017/?gssapiServiceName=mongodb Implicit session: session { "id" : UUID("c0337c02-7ee2-45d9-9349-b22d6b1ffe85") } MongoDB server version: 4.0.5 server should be down... 2019-03-14T21:56:10.327+0530 I NETWORK [js] trying reconnect to 127.0.0.1:27017 failed 2019-03-14T21:56:11.331+0530 I NETWORK [js] reconnect 127.0.0.1:27017 failed failed 2019-03-14T21:56:11.333+0530 I QUERY [js] ... Read More

166 Views
Let us firs create a tablemysql> create table LimitWithStoredProcedure -> ( -> Id int NOT NULL AUTO_INCREMENT PRIMARY KEY, -> Name varchar(10) -> ); Query OK, 0 rows affected (0.47 sec)Insert some records in the table using insert command.The query is as followsmysql> insert into LimitWithStoredProcedure(Name) values('John'); Query OK, 1 row affected (0.15 sec) mysql> insert into LimitWithStoredProcedure(Name) values('Chris'); Query OK, 1 row affected (0.15 sec) mysql> insert into LimitWithStoredProcedure(Name) values('Maxwell'); Query OK, 1 row affected (0.28 sec) mysql> insert into LimitWithStoredProcedure(Name) values('Bob'); Query OK, 1 row affected (0.24 sec) mysql> insert into LimitWithStoredProcedure(Name) values('David'); Query ... Read More

721 Views
To list all databases in the Mongo shell, you need to use show command. The syntax is as follows −show dbs;Let us implement the above syntax for MongoDB. The query is as follows −> show dbs;The following is the output −admin 0.000GB config 0.000GB local 0.000GB sample 0.000GB sampleDemo 0.000GB test 0.003GBIf you create a new database in MongoDB then it won’t be present in list of databases.Let us check the same. Create a new database −> use studentTracker; switched to db studentTrackerNow list all the databases from Mongo shell. The query is as follows −> show dbs;The following is ... Read More

572 Views
The syntax is as followsupdate yourTableName set yourColumnName1=yourValue where yourColumnName2=yourValue order by yourIdColumnName DESC LIMIT 1;To understand the above syntax, let us create a table. The query to create a table is as followsmysql> create table UpdateWithHighestDemo -> ( -> UserId int NOT NULL AUTO_INCREMENT PRIMARY KEY, -> UserStatus tinyint, -> UserRank int -> ); Query OK, 0 rows affected (0.61 sec)Insert some records in the table using insert command.The query is as followsmysql> insert into UpdateWithHighestDemo(UserStatus, UserRank) values(1, 78); Query OK, 1 row affected (0.12 sec) mysql> insert into UpdateWithHighestDemo(UserStatus, UserRank) values(0, 118); Query ... Read More

1K+ Views
You can use format() function for the separators. It will work in MySQL version greater than or equal to 5.5. We are using the version 8.0.12mysql> select version(); +-----------+ | version() | +-----------+ | 8.0.12 | +-----------+ 1 row in set (0.00 sec)The syntax is as followsSELECT FORMAT(yourColumnName, valueAfterDecimalPoint, 'de_DE') AS anyAliasNamefrom yourTableName;To understand the above syntax, let us create a table. The query to create a table is as followsmysql> create table formatNumberDemo -> ( -> Id int NOT NULL AUTO_INCREMENT PRIMARY KEY, -> Number DECIMAL(19, 1) ... Read More

7K+ Views
To convert number INT in minutes to TIME in MySQL, you can use SEC_TO_TIME() function.The syntax is as followsselect SEC_TO_TIME(yourIntColumnName*60) AS `anyAliasName` from yourTableName;To understand the above syntax, let us create a table. The query to create a table is as followsmysql> create table convertNumberToMinute -> ( -> Id int NOT NULL AUTO_INCREMENT PRIMARY KEY, -> NumberToMinute int -> ); Query OK, 0 rows affected (0.79 sec)Insert some records in the table using insert command.The query is as followsmysql> insert into convertNumberToMinute(NumberToMinute) values(60); Query OK, 1 row affected (0.12 sec) mysql> insert into convertNumberToMinute(NumberToMinute) values(70); Query ... Read More