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Articles by George John
Page 40 of 79
How can I change root username in MySQL?
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 MoreReplace 0 with null in MySQL?
You can use NULLIF() from MySQL to replace 0 with NULL. The syntax is as follows −SELECT *, NULLIF(yourColumnName, 0) as anyVariableName from yourTableName;To understand the above syntax, let us create a table. The query to create a table is as follows −mysql> create table Replace0WithNULLDemo -> ( -> Id int NOT NULL auto_increment, -> Name varchar(20), -> Marks int, -> PRIMARY KEY(Id) -> ); Query OK, 0 rows affected (0.53 sec)Now you can insert some records in the table using insert command. The query is as follows −mysql> insert into Replace0WithNULLDemo(Name, Marks) values('John', ...
Read MoreMySQL LIMIT to select a single row
To select a single row in MySQL, you can use LIMIT. At first, let us create a table. The query to create a table is as follows −mysql> create table selectWithPrimaryKey -> ( -> Id int NOT NULL AUTO_INCREMENT, -> Name varchar(20), -> Age int, -> Marks int, -> PRIMARY KEY(Id) -> ); Query OK, 0 rows affected (0.78 sec)Insert some records in the table using insert command. The query is as follows −mysql> insert into selectWithPrimaryKey(Name, Age, Marks) values('Larry', 24, 98); Query OK, 1 row affected (0.15 sec) mysql> insert into ...
Read MoreMySQL order by string with numbers?
To MySQL order string with numbers, the following is the syntax, wherein we have used ORDER BY, SUBSTR() and CAST() −SELECT *FROM yourTableName ORDER BY SUBSTR(yourColumnName FROM 1 FOR 2), CAST(SUBSTR(yourColumnName FROM 2) AS UNSIGNED);To understand the above syntax, let us create a table. The query to create a table is as follows −mysql> create table OrderByStringWithNumbers -> ( -> Id int NOT NULL AUTO_INCREMENT, -> Words varchar(10), -> PRIMARY KEY(Id) -> ); Query OK, 0 rows affected (0.86 sec)Insert some records in the table using insert command. The query is as follows −mysql> insert ...
Read MoreMySQL select * with distinct id?
You can use GROUP BY command for select with distinct id. The syntax is as follows −SELECT *FROM yourTableName GROUP BY yourColumnName;To understand the above syntax, let us create a table. The query to create a table is as follows −mysql> create table DistinctIdDemo -> ( -> Id int, -> Name varchar(20), -> Age int -> ); Query OK, 0 rows affected (1.03 sec)Insert some records in the table using insert command. Here, we have added ID with duplicate values.The query is as follows −mysql> insert into DistinctIdDemo values(1, 'Mike', 23); Query OK, 1 row ...
Read MoreSelect distinct combinations from two columns in MySQL?
To select distinct combinations from two columns, you can use CASE statement. Let us create a table with some columns.The query to create a table is as follows −mysql> create table select_DistinctTwoColumns -> ( -> Id int NOT NULL AUTO_INCREMENT, -> FirstValue char(1), -> SecondValue char(1), -> PRIMARY KEY(Id) -> ); Query OK, 0 rows affected (0.57 sec)Now you can insert some records in the table using insert command. The query is as follows −mysql> insert into select_DistinctTwoColumns(FirstValue, SecondValue) values('s', 't'); Query OK, 1 row affected (0.12 sec) mysql> insert into select_DistinctTwoColumns(FirstValue, SecondValue) ...
Read MoreOrder by last 3 chars in MySQL?
You can use ORDER BY RIGHT() function to order by last 3 chars in MySQL. The syntax is as follows −SELECT *FROM yourTableName ORDER BY RIGHT(yourColumnName, 3) yourSortingOrder;Just replace the ‘yourSortingOrder’ to ASC or DESC to set the ascending or descending order respectively.To understand the above syntax, let us create a table. The query to create a table is as follows −mysql> create table OrderByLast3Chars -> ( -> EmployeeId int NOT NULL AUTO_INCREMENT, -> EmployeeName varchar(20), -> EmployeeAge int, -> PRIMARY KEY(EmployeeId) -> ); Query OK, 0 rows affected (0.56 sec)Insert some records in ...
Read MoreWhat are intent-filters in Android?
An intent filter is an instance of the IntentFilter class. Intent filters are helpful while using implicit intents, It is not going to handle in java code, we have to set it up in AndroidManifest.xml. Android must know what kind of intent it is launching so intent filters give the information to android about intent and actions.Before launching intent, android going to do action test, category test and data test. This example demonstrate about how to use intent filters in android.Step 1 − Create a new project in Android Studio, go to File ⇒ New Project and fill all required ...
Read MoreHow to add line break for UILabel in iOS/iPhone?
Line break in a UILabel is used to change how the text appears on a label. Suppose a label has text more than two lines but by default the Line break in a UILabel is used to change how the text appears on a label. Suppose a label has text more than two lines but by default the label shows 1 line and wraps/ trims the text that’s more than the label size.This can be done in multiple ways. Three of them are mentioned below.On the storyboard add a label.Give top constraint, trailing and leading constraint.Method One − Editing with ...
Read MoreWhat is the MySQL user creation script?
First, create a user and password using CREATE command. The syntax is as follows.CREATE USER 'yourUserName'@'localhost' IDENTIFIED BY 'yourPassword';The syntax to give all privileges of the specific database to the user is as follows.GRANT ALL PRIVILEGES ON yourDatabaseName . * TO 'yourUserName'@'localhost';Now you can implement the above syntaxes to create a user and grant all privileges.Step 1 − Create a userThe query is as follows.mysql> create user 'Adam Smith'@'localhost' IDENTIFIED BY 'Adam123456'; Query OK, 0 rows affected (0.29 sec)Step 2 − Grant all privileges to the user.The query is as follows.mysql> GRANT ALL PRIVILEGES ON test . * TO 'Adam ...
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