Found 4378 Articles for MySQL

Count occurrences of known distinct values in MySQL

AmitDiwan
Updated on 02-Jul-2020 12:25:57

159 Views

For this, you can use aggregate function SUM(). Let us first create a table −mysql> create table DemoTable636 (    StudentId int NOT NULL AUTO_INCREMENT PRIMARY KEY, StudentFirstName varchar(100) ); Query OK, 0 rows affected (0.51 sec)Insert some records in the table using insert command −mysql> insert into DemoTable636(StudentFirstName) values('John'); Query OK, 1 row affected (0.18 sec) mysql> insert into DemoTable636(StudentFirstName) values('Robert'); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable636(StudentFirstName) values('Robert'); Query OK, 1 row affected (0.22 sec) mysql> insert into DemoTable636(StudentFirstName) values('Sam'); Query OK, 1 row affected (0.20 sec) mysql> insert into DemoTable636(StudentFirstName) values('Mike'); Query OK, ... Read More

Implement two conditions for a single column in MySQL for null and empty value

AmitDiwan
Updated on 23-Aug-2019 08:27:21

95 Views

Let us first create a table −mysql> create table DemoTable635(    EmployeId int NOT NULL AUTO_INCREMENT PRIMARY KEY, EmployeeName varchar(100) ); Query OK, 0 rows affected (1.24 sec)Insert some records in the table using insert command −mysql> insert into DemoTable635(EmployeeName) values('John'); Query OK, 1 row affected (0.20 sec) mysql> insert into DemoTable635(EmployeeName) values('Sam'); Query OK, 1 row affected (0.27 sec) mysql> insert into DemoTable635(EmployeeName) values(''); Query OK, 1 row affected (0.38 sec) mysql> insert into DemoTable635(EmployeeName) values(null); Query OK, 1 row affected (0.12 sec) mysql> insert into DemoTable635(EmployeeName) values('David'); Query OK, 1 row affected (0.22 sec)Display all records from the ... Read More

MySQL query to display ranks of multiple columns?

AmitDiwan
Updated on 23-Aug-2019 08:09:28

303 Views

For this, use FIND_IN_SET() method. Let us first create a table −mysql> create table DemoTable634 (FirstName varchar(100), Marks int, Age int); Query OK, 0 rows affected (0.69 sec)Insert some records in the table using insert command −mysql> insert into DemoTable634 values('John', 60, 23); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable634 values('Chris', 80, 21); Query OK, 1 row affected (0.23 sec) mysql> insert into DemoTable634 values('Robert', 70, 24); Query OK, 1 row affected (0.22 sec)Display all records from the table using select statement −mysql> select *from DemoTable634;This will produce the following output −+-----------+-------+------+ | FirstName | Marks ... Read More

Update a table based on StudentId value in MySQL?

AmitDiwan
Updated on 23-Aug-2019 08:05:49

120 Views

Let us first create a table −mysql> create table DemoTable633 (StudentId char(2) not null primary key, StudentName varchar(100)); Query OK, 0 rows affected (1.06 sec)Insert some records in the table using insert command −mysql> insert into DemoTable633 values('10', 'Chris'); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable633 values('20', 'Sam'); Query OK, 1 row affected (0.18 sec) mysql> insert into DemoTable633 values('30', 'David'); Query OK, 1 row affected (0.17 sec)Display all records from the table using select statement −mysql> select *from DemoTable633;This will produce the following output −+-----------+-------------+ | StudentId | StudentName | +-----------+-------------+ | 10     ... Read More

Display MySQL histogram with negative values?

AmitDiwan
Updated on 02-Jul-2020 12:29:23

111 Views

For negative values, use reverse() along with concat(). Let us first create a table −mysql> create table DemoTable632 (    histogramId int NOT NULL AUTO_INCREMENT PRIMARY KEY, histogramValue int, histogramImage text ); Query OK, 0 rows affected (0.78 sec)Insert some records in the table using insert command −mysql> insert into DemoTable632(histogramValue) values(2); Query OK, 1 row affected (0.12 sec) mysql> insert into DemoTable632(histogramValue) values(3); Query OK, 1 row affected (0.34 sec) mysql> insert into DemoTable632(histogramValue) values(-6); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable632(histogramValue) values(-5); Query OK, 1 row affected (0.13 sec)Display all records from the table ... Read More

Storing value from a MySQL SELECT statement to a variable?

AmitDiwan
Updated on 23-Aug-2019 07:54:46

539 Views

Let us first create a table −mysql> create table DemoTable631 (    StudentId int NOT NULL AUTO_INCREMENT PRIMARY KEY, StudentName varchar(100) ); Query OK, 0 rows affected (0.83 sec)Insert some records in the table using insert command −mysql> insert into DemoTable631(StudentName) values('John Smith'); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable631(StudentName) values('Adam Smith'); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable631(StudentName) values('David Miller'); Query OK, 1 row affected (0.16 sec)Display all records from the table using select statement −mysql> select *from DemoTable631;This will produce the following output −+-----------+--------------+ | StudentId | StudentName | ... Read More

How to update the date format in MySQL?

AmitDiwan
Updated on 23-Aug-2019 07:51:27

533 Views

Let us first create a table −mysql> create table DemoTable630 (ArrivalDate varchar(100)); Query OK, 0 rows affected (0.55 sec)Insert some records in the table using insert command −mysql> insert into DemoTable630 values('2015-21-01'); Query OK, 1 row affected (0.09 sec) mysql> insert into DemoTable630 values('2018-25-12'); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable630 values('2019-15-07'); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable630 values('2016-31-03'); Query OK, 1 row affected (0.17 sec)Display all records from the table using select statement −mysql> select *from DemoTable630;This will produce the following output −+-------------+ | ArrivalDate | +-------------+ | 2015-21-01  | ... Read More

How to escape '%' character on the left and middle part of strings in a MySQL column?

AmitDiwan
Updated on 23-Aug-2019 07:48:55

105 Views

Let us first create a table −mysql> create table DemoTable629 (StudentId int NOT NULL AUTO_INCREMENT PRIMARY KEY, StudentSubject text); Query OK, 0 rows affected (0.77 sec)Insert some records in the table using insert command −mysql> insert into DemoTable629(StudentSubject) values('MySQL%'); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable629(StudentSubject) values('Spring%Hibernate'); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable629(StudentSubject) values('%Java'); Query OK, 1 row affected (0.21 sec)Display all records from the table using select statement −mysql> select *from DemoTable629;This will produce the following output −+-----------+------------------+ | StudentId | StudentSubject   | +-----------+------------------+ |         ... Read More

MySQL to get only the floating-point numbers from a list of values in a column

AmitDiwan
Updated on 23-Aug-2019 07:38:43

389 Views

Let us first create a table −mysql> create table DemoTable628 (Value DECIMAL(10, 2)); Query OK, 0 rows affected (0.52 sec)Insert some records in the table using insert command −mysql> insert into DemoTable628 values(10.97); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable628 values(20.04); Query OK, 1 row affected (0.18 sec) mysql> insert into DemoTable628 values(12.00); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable628 values(89.56); Query OK, 1 row affected (0.20 sec)Display all records from the table using select statement −mysql> select *from DemoTable628;This will produce the following output −+-------+ | Value | +-------+ | 10.97 ... Read More

Convert the case of every value in a MySQL Column to uppercase

AmitDiwan
Updated on 23-Aug-2019 07:32:02

244 Views

For this, use UPPER() on MySQL column. Let us first create a table −mysql> create table DemoTable627 (Id int NOT NULL AUTO_INCREMENT PRIMARY KEY, FirstName varchar(100)); Query OK, 0 rows affected (0.62 sec)Insert some records in the table using insert command −mysql> insert into DemoTable627(FirstName) values(UPPER('John')); Query OK, 1 row affected (0.11 sec) mysql> insert into DemoTable627(FirstName) values(UPPER('Sam')); Query OK, 1 row affected (0.11 sec) mysql> insert into DemoTable627(FirstName) values(UPPER('Mike')); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable627(FirstName) values(UPPER('Carol')); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable627(FirstName) values(UPPER('dAVID')); Query OK, 1 row affected (0.70 ... Read More

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