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Strings in C# String is immutable in C# that would mean you couldn’t modify it after it is created. It creates a new object of string type in memory if you will perform any operation. string str1 = "Welcome!"; // creates a new string instance str1 += "Hello"; str1 += "World”; StringBuilder in C# StringBuilder is mutable in C#. This means that if an operation is performed on the string, it will not create a new instance every time. With that, it will not create new space in memory, unlike Strings. StringBuilder str1 = new StringBuilder(""); str1.Append("Welcome!"); ... Read More
Function-based index wasn’t possible in MySQL versions below 5.6. Firstly, to create function-based index in MySQL, we will create a table. mysql> create table FunctionIndexDemo - > ( - > FirstName varchar(100) - > ); Query OK, 0 rows affected (0.70 sec) Let us see the syntax to create a function based index. create index index_name on yourTableName (column_name(IntegerSize)); Here is the query. mysql> create index indFirstName on FunctionIndexDemo (FirstName(6)); Query OK, 0 rows affected (0.56 sec) Records: 0 Duplicates: 0 Warnings: 0 ... Read More
The MySQL’s DESCRIBE or DESC both are equivalent. The DESC is the short form of DESCRIBE command and used to dipslay the information about a table like column names and constraints on column name. The DESCRIBE command is equivalent to the following command − SHOW columns from yourTableName command. The following is the query that display information about a table with the help of DESCRIBE command. The query is as follows. mysql> DESCRIBE Student; Above, Student is the table name in my database. The above query generates the following output. +-------+--------------+------+-----+---------+-------+ | Field | Type ... Read More
To print m multiples of n, first set the value of m and n − int n = 6, m = 1; Now loop through the value of m, increment it and multiply with n on every iteration − while (m
C++ is a statically typed, compiled, general-purpose, case-sensitive, free-form programming language that supports procedural, object-oriented, and generic programming. C++ is regarded as a middle-level language, as it comprises a combination of both high-level and low-level language features. C# is a simple, modern, general-purpose, object-oriented programming language developed by Microsoft within its .NET initiative led by Anders Hejlsberg. The following are the differences between C++and C#. Memory Management C++ has manual memory management, whereas memory management is handled automatically in C#. Platforms C++ can be run on different platforms whereas C# is generally used only on Windows. Faster code C++ code ... Read More
Here given a password, our task is to check that this Password is valid or not. Here we use re module that provide regular expression and re.search() is used for checking the validation of alphabets, digits or special characters. Algorithm Step 1: first we take an alphanumeric string as a password. Step 2: first check that this string should minimum 8 characters. Step 3: the alphabets must be between a-z. Step 4: At least one alphabet should be in Uppercase A-Z. Step 5: At least 1 number or digit between 0-9. Step 6: At least 1 character from [_ ... Read More
You can enable ONLY_FULL_GROUP_BY in MySQL as shown in the following query − mysql> SET sql_mode = 'ONLY_FULL_GROUP_BY'; Query OK, 0 rows affected (0.01 sec) As shown above, we can enable ONLY_FULL_GROUP_BY with the help of SET command. To disable ONLY_FULL_GROUP_BY with the help of the following query − mysql> SET GLOBAL sql_mode=(SELECT REPLACE(@@sql_mode,'ONLY_FULL_GROUP_BY','')); Query OK, 0 rows affected (0.04 sec) We have disabled ONLY_FULL_GROUP_BY successfully.
To create a MySQL table with MyISAM engine, we can use ENGINE command. Let us first create a table using CREATE command. mysql> create table StudentRecordWithMyISAM -> ( -> Id int, -> StudentName varchar(100), -> StudentAge int -> )ENGINE=MyISAM; Query OK, 0 rows affected (0.26 sec) Above, we have set the ENGINE as “MyISAM”. To check how many columns are present in the table, use DESC command. mysql> DESC StudentRecordWithMyISAM; The following is the output. +-------------+--------------+------+-----+---------+-------+ | Field ... Read More
For our example, let us create a table with NOT NULL constraint. After that, we will modify a column to allow NULL. The following is the query to create a table with NOT NULL constraint. mysql> create table AllowNullDemo -> ( -> id int not null -> ); Query OK, 0 rows affected (0.48 sec)= Insert records with the help of INSERT command. The query is as follows. mysql> insert into AllowNullDemo values(); Query OK, 1 row affected, 1 warning (0.19 sec) mysql> insert into AllowNullDemo values(); ... Read More
Python provides openpyxl module for operating with Excel files. How to create Excel files, how to write, read etc. can be implemented by this module. For installing openpyxl module, we can write this command in command prompt pip install openpyxl If we want to give a sheet title name Example code import openpyxl my_wb = openpyxl.Workbook() my_sheet = my_wb.active my_sheet_title = my_sheet.title print("My sheet title: " + my_sheet_title) Output My sheet title:Sheet To change Title Name Example code import openpyxl my_wb = openpyxl.Workbook() my_sheet = my_wb.active my_sheet.title = "My New Sheet" print("sheet name ... Read More