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Found 6705 Articles for Database

272 Views
Let us first create a table and set default values −mysql> create table DemoTable803(UserId int DEFAULT 101, UserName varchar(100) DEFAULT 'Chris'); Query OK, 0 rows affected (1.18 sec)Insert some records in the table using insert command. For the values we are not inserting, the default values will get set automatically −mysql> insert into DemoTable803 values(102, 'Chris'); Query OK, 1 row affected (0.34 sec) mysql> insert into DemoTable803(UserName) values('Mike'); Query OK, 1 row affected (0.48 sec) mysql> insert into DemoTable803(UserId) values(103); Query OK, 1 row affected (0.21 sec) mysql> insert into DemoTable803 values(); Query OK, 1 row affected (0.22 sec) mysql> ... Read More

200 Views
To extract from datetime column, you can use date() along with trim(). Here, trim() is used to remove whitespace while comparing. Let us first create a table −mysql> create table DemoTable661(Duedate datetime); Query OK, 0 rows affected (0.57 sec)Insert some records in the table using insert command −mysql> insert into DemoTable661 values(' 2019-01-21 12:02:21'); Query OK, 1 row affected (0.10 sec) mysql> insert into DemoTable661 values(' 2019-07-11 11:55:59 '); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable661 values('2019-11-21 04:00:59 '); Query OK, 1 row affected (0.10 sec)Display all records from the table using select statement −mysql> select ... Read More

310 Views
Yes, you can use date_sub() to subtract number of days from a date. Following is the syntax −select date_sub(yourColumnName, Interval yourAmountOfDays day) from yourTableName;Let us first create a table −mysql> create table DemoTable660(AdmissionDate datetime); Query OK, 0 rows affected (0.82 sec)Insert some records in the table using insert command −mysql> insert into DemoTable660 values('2018-01-24'); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable660 values('2019-07-10'); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable660 values('2020-11-20'); Query OK, 1 row affected (0.59 sec)Display all records from the table using select statement −mysql> select *from DemoTable660;This will produce the ... Read More

69 Views
To fetch a specific row when values are the same, use GROUP BY. Let us first create a table −mysql> create table DemoTable659(Id int, Name varchar(100), Score int); Query OK, 0 rows affected (0.52 sec)Insert some records in the table using insert command −mysql> insert into DemoTable659 values(11, 'John', 45); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable659 values(15, 'John', 59); Query OK, 1 row affected (0.20 sec) mysql> insert into DemoTable659 values(15, 'Sam', 61); Query OK, 1 row affected (0.14 sec)Display all records from the table using select statement −mysql> select *from DemoTable659;This will produce the ... Read More

329 Views
Let us first create a table −mysql> create table DemoTable658(FirstName varchar(100),value char(2)); Query OK, 0 rows affected (0.95 sec)Insert some records in the table using insert command −mysql> insert into DemoTable658(FirstName) values('John') ; Query OK, 1 row affected (0.19 sec) mysql> insert into DemoTable658(value,FirstName) values(default(value),'Sam'); Query OK, 1 row affected (0.23 sec)Display all records from the table using select statement −mysql> select *from DemoTable658;This will produce the following output −+-----------+-------+ | FirstName | value | +-----------+-------+ | John | NULL | | Sam | NULL | +-----------+-------+ 2 rows in set (0.00 sec)

799 Views
Here, we are converting time value, for example 150:50:10 to days and hours form, i.e. 6 days 6 hours.You can use CONCAT() along with HOUR() for this. Let us first create a table −mysql> create table DemoTable657(DueTime time); Query OK, 0 rows affected (3.68 sec)Insert some records in the table using insert command. Here, we have inserted the records in the form of total hours −mysql> insert into DemoTable657 values('120:30:00'); Query OK, 1 row affected (0.38 sec) mysql> insert into DemoTable657 values('150:50:10'); Query OK, 1 row affected (0.27 sec)Display all records from the table using select statement −mysql> select *from ... Read More

174 Views
You can use SELECT *FROM yourTableName in stored procedure. Let us first create a table −mysql> create table DemoTable654 ( StudentId int NOT NULL AUTO_INCREMENT PRIMARY KEY, StudentFirstName varchar(100) ); Query OK, 0 rows affected (0.70 sec)Insert some records in the table using insert command −mysql> insert into DemoTable654(StudentFirstName) values('John'); Query OK, 1 row affected (0.11 sec) mysql> insert into DemoTable654(StudentFirstName) values('Sam'); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable654(StudentFirstName) values('Mike'); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable654(StudentFirstName) values('Robert'); Query OK, 1 row affected (0.12 sec)Display all records from the table using ... Read More

471 Views
To change order of items in MySQL, use ORDER BY alias name. Let us first create a table −mysql> create table DemoTable653 (Product1Amount int, Product2Amount int); Query OK, 0 rows affected (0.42 sec)Insert some records in the table using insert command −mysql> insert into DemoTable653 values(400, 250); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable653 values(500, 300); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable653 values(40, 400); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable653 values(200, 450); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable653 values(50, 20); Query ... Read More

466 Views
Let us first create a table −mysql> create table DemoTable651 (Id int NOT NULL AUTO_INCREMENT PRIMARY KEY, Value varchar(100)); Query OK, 0 rows affected (0.59 sec)Insert some records in the table using insert command −mysql> insert into DemoTable651(Value) values('Title'); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable651(Value) values('course'); Query OK, 1 row affected (0.26 sec) mysql> insert into DemoTable651(Value) values('subject'); Query OK, 1 row affected (0.20 sec)Display all records from the table using select statement −mysql> select *from DemoTable651;This will produce the following output −+----+---------+ | Id | Value | +----+---------+ | 1 | ... Read More

302 Views
For this, use aggregate function COUNT(). Let us first create a table −mysql> create table DemoTable650 (Value1 int, Value2 int); Query OK, 0 rows affected (0.83 sec)Insert some records in the table using insert command −mysql> insert into DemoTable650 values(100, 500); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable650 values(100, 500); Query OK, 1 row affected (0.10 sec) mysql> insert into DemoTable650 values(100, 500); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable650 values(100, 500); Query OK, 1 row affected (0.23 sec) mysql> insert into DemoTable650 values(200, 500); Query OK, 1 row affected (0.12 sec)Display ... Read More