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For this, you can use the CASE statement along with SUM(). Here, we will be finding the count of Male and Female records from a column with employee gender values. Let us first create a table −mysql> create table DemoTable ( EmployeeGender ENUM('Male', 'Female') ); Query OK, 0 rows affected (0.52 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('Male'); Query OK, 1 row affected (0.19 sec) mysql> insert into DemoTable values('Female'); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable values('Male'); Query OK, 1 row affected (0.10 sec) mysql> insert into ... Read More
The @ symbol in a stored procedure can be used for user-defined session variables. Let us first create a table −mysql> create table DemoTable ( StudentName varchar(50) ); Query OK, 0 rows affected (1.30 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('John Smith'); Query OK, 1 row affected (1.00 sec) mysql> insert into DemoTable values('John Doe'); Query OK, 1 row affected (0.19 sec) mysql> insert into DemoTable values('Chris Brown'); Query OK, 1 row affected (0.53 sec)Display all records from the table using select statement −mysql> select *from DemoTable;This will produce the following output ... Read More
Let us first create a table −mysql> create table DemoTable ( FirstName varchar(100), LastName varchar(100) ); Query OK, 0 rows affected (0.83 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('Adam', 'Smith'); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable values('John', 'Doe'); Query OK, 1 row affected (0.11 sec) mysql> insert into DemoTable values('John', 'Smith'); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable values('Chris', 'Brown'); Query OK, 1 row affected (0.08 sec) mysql> insert into DemoTable values('Robert', 'Brown'); Query OK, 1 row affected (0.10 sec) mysql> insert ... Read More
There are two ways to go about replacing \ with \ or unescaping backslash escaped strings in Python. First is using literal_eval to evaluate the string. Note that in this method you need to surround the string in another layer of quotes. For example:>>> import ast >>> a = '"Hello,world"' >>> print ast.literal_eval(a) Hello, worldAnother way is to use the decode('string_escape') method from the string class. For example,>>> print "Hello,world".decode('string_escape') Hello, world
For this, you can use the property IS NULL for null values in MySQL. Let us first create a table −mysql> create table DemoTable ( Name varchar(100) ); Query OK, 0 rows affected (0.53 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('Robert'); Query OK, 1 row affected (0.23 sec) mysql> insert into DemoTable values(null); Query OK, 1 row affected (0.10 sec) mysql> insert into DemoTable values('David'); Query OK, 1 row affected (0.12 sec) mysql> insert into DemoTable values(null); Query OK, 1 row affected (0.11 sec) mysql> insert into DemoTable values('Robert'); Query OK, 1 ... Read More
Let us first create a table −mysql> create table DemoTable ( Id int, ColorName varchar(100) ); Query OK, 0 rows affected (0.56 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values(100, 'Red'); Query OK, 1 row affected (0.11 sec) mysql> insert into DemoTable values(101, 'Green'); Query OK, 1 row affected (0.20 sec) mysql> insert into DemoTable values(101, 'Blue'); Query OK, 1 row affected (0.28 sec) mysql> insert into DemoTable values(102, 'Yellow'); Query OK, 1 row affected (0.18 sec) mysql> insert into DemoTable values(100, 'Purple'); Query OK, 1 row affected (0.12 sec) mysql> insert ... Read More
Let us first create a table. Here, we have VARCHAR type for value −mysql> create table DemoTable ( Value varchar(100) ); Query OK, 0 rows affected (1.80 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('100'); Query OK, 1 row affected (0.20 sec) mysql> insert into DemoTable values('1244'); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable values('15789'); Query OK, 1 row affected (0.18 sec)Display all records from the table using select statement −mysql> select *from DemoTable;This will produce the following output −+-------+ | Value | +-------+ | 100 | ... Read More
Let us first create a table −mysql> create table DemoTable ( Id int NOT NULL AUTO_INCREMENT PRIMARY KEY, AddDay int, PostDate date ); Query OK, 0 rows affected (2.73 sec)Insert some records in the table using insert command −mysql> insert into DemoTable(AddDay, PostDate) values(20, '2019-08-04'); Query OK, 1 row affected (0.11 sec) mysql> insert into DemoTable(AddDay, PostDate) values(7, '2019-08-20'); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable(AddDay, PostDate) values(45, '2019-07-01'); Query OK, 1 row affected (0.19 sec)Display all records from the table using select statement −mysql> select *from DemoTable;This will produce the following output ... Read More
Let us first create a table −mysql> create table DemoTable ( Price int, Quantity int ); Query OK, 0 rows affected (0.71 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values(45, 3); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable values(90, 2); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable values(440, 1); Query OK, 1 row affected (0.09 sec)Display all records from the table using select statement −mysql> select *from DemoTable;This will produce the following output −+-------+----------+ | Price | Quantity | +-------+----------+ | ... Read More
Let us first create a table −mysql> create table DemoTable1 ( Id int NOT NULL AUTO_INCREMENT PRIMARY KEY, Name varchar(100) ); Query OK, 0 rows affected (0.59 sec)Insert some records in the table using insert command −mysql> insert into DemoTable1(Name) values('Chris'); Query OK, 1 row affected (0.10 sec) mysql> insert into DemoTable1(Name) values('Robert'); Query OK, 1 row affected (0.19 sec) mysql> insert into DemoTable1(Name) values('Mike'); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable1(Name) values('Sam'); Query OK, 1 row affected (0.07 sec)Display all records from the table using select statement −mysql> select *from DemoTable1;This will produce ... Read More