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To split a column after specific characters, use the SUBSTRING_INDEX() method −select substring_index(yourColumnName, '-', -1) AS anyAliasName from yourTableName;Let us first create a table −mysql> create table DemoTable -> ( -> StreetName text -> ); Query OK, 0 rows affected (0.60 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('Paris Hill St.-CA-83745646') ; Query OK, 1 row affected (0.32 sec) mysql> insert into DemoTable values('502 South Armstrong Street-9948443'); Query OK, 1 row affected (0.20 sec)Display all records from the table using select statement −mysql> select *from DemoTable;OutputThis will produce the following output −+------------------------------------+ | ... Read More
Let us first create a table −mysql> create table DemoTable1 -> ( -> Id int, -> Name varchar(100) -> ); Query OK, 0 rows affected (0.53 sec)Insert some records in the table using insert command −mysql> insert into DemoTable1 values(10, 'John'); Query OK, 1 row affected (0.23 sec) mysql> insert into DemoTable1 values(11, 'Chris'); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable1 values(12, 'Robert'); Query OK, 1 row affected (0.32 sec)Display all records from the table using select statement −mysql> select *from DemoTable;OutputThis will produce the following output −+------+--------+ | Id ... Read More
Use the CASE statements and set conditions for the same. Let us first create a table −mysql> create table DemoTable -> ( -> X int, -> Y int -> ); Query OK, 0 rows affected (0.57 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values(20, 30); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable values(40, 15); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable values(80, 85); Query OK, 1 row affected (0.13 sec)Display all records from the table using select statement −mysql> select ... Read More
To display structure of a table, following is the syntax −show create table yourTableName;Let us first create a table −mysql> create table DemoTable -> ( -> Id int NOT NULL AUTO_INCREMENT PRIMARY KEY, -> EmployeeFirstName varchar(100), -> EmployeeLastName varchar(100), -> EmployeeAge int, -> isMarried tinyint(1), -> EmployeeAddress varchar(100), -> EmployeeCountryName varchar(100) -> ); Query OK, 0 rows affected (0.62 sec)Here is the query to display structure −mysql> show create table DemoTable;OutputThis will produce the following output −+--------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ | Table | Create Table ... Read More
Let us first create a table −mysql> create table DemoTable -> ( -> ArrivalDate datetime -> ); Query OK, 0 rows affected (0.91 sec)Insert some records in the table using insert command. Let’s say the current date is 2019-07-03 −mysql> insert into DemoTable values('2019-07-03'); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable values('2019-06-20'); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable values('2019-06-15'); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable values('2018-06-11'); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable values('2018-06-01'); Query ... Read More
Let us first create a table −mysql> create table DemoTable -> ( -> Id int, -> Value int -> ); Query OK, 0 rows affected (0.68 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values(100, 85885); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable values(101, 885995474); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable values(100, 895943); Query OK, 1 row affected (0.20 sec)Display all records from the table using select statement −mysql> select *from DemoTable;OutputThis will produce the following output −+------+-----------+ | Id ... Read More
The statistics module of Python library consists of functions to calculate statistical formulae using numeric data types including Fraction and Decimal types.Following import statement is needed to use functions described in this article.>>> from statistics import *Following functions calculate the central tendency of sample data.mean() − This function calculates the arithmetic mean of data in the form of sequence or iterator.>>> from statistics import mean >>> numbers = [12, 34, 21, 7, 56] >>> mean(numbers) 26The sample data may contain Decimal object or Fraction object>>> from decimal import Decimal >>> numbers = [12, 34, 21, Decimal('7'), 56] >>> mean(numbers) Decimal('26') ... Read More
Let us first create a table −mysql> create table DemoTable -> ( -> Value int -> ); Query OK, 0 rows affected (0.80 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values(10); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable values(20); Query OK, 1 row affected (0.12 sec) mysql> insert into DemoTable values(100); Query OK, 1 row affected (0.14 sec)Display all records from the table using select statement −mysql> select *from DemoTable;OutputThis will produce the following output −+-------+ | Value | +-------+ | 10 | | ... Read More
To order by number of chars, use ORDER BY and LENGTH() method. Following is the syntax −select *from yourTableName order by LENGTH(yourColumnName) DESC;Let us first create a table −mysql− create table DemoTable -> ( -> Name varchar(100) -> ); Query OK, 0 rows affected (0.50 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('John'); Query OK, 1 row affected (0.12 sec) mysql> insert into DemoTable values('Robert'); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable values('Bob'); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable ... Read More
Use group_concat() function from MySQL to concatenate. Let us first create a table −mysql> create table DemoTable -> ( -> Subject varchar(10) -> ); Query OK, 0 rows affected (0.43 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('C'); Query OK, 1 row affected (0.20 sec) mysql> insert into DemoTable values('C++'); Query OK, 1 row affected (0.25 sec) mysql> insert into DemoTable values('C++'); Query OK, 1 row affected (0.06 sec) mysql> insert into DemoTable values('MongoDB'); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable values('MySQL'); Query ... Read More