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In case of updateable views, it is quite possible that we update the data that is not visible through the view because we create a view to revealing only the partial data of a table. Such kind of updates makes the view inconsistent. We can ensure the consistency of views by using WITH CHECK OPTION while creating or modifying the views. Although WITH CHECK OPTION clause is an optional part of CREATE VIEW statement but it is very useful to make views consistent.Basically, the WITH CHECK OPTION clause prevents us from updating or inserting the rows which are not visible ... Read More
Declare a string and add elements −string[] str = { "One", "Two", "Three", "Four", "Five" };Use the Join() method to join the words−string res = string.Join(" ", str);Let us see the complete code −Example Live Demousing System; public class Demo { public static void Main() { string[] str = { "One", "Two", "Three", "Four", "Five" }; // join words string res = string.Join(" ", str); Console.WriteLine(res); } }OutputOne Two Three Four Five
The following is the string array −string[] str = { "Java", "AngularJS", "Python", "jQuery", "HTML5" };Firstly, join it −string.Join(" ", str);Now to separate the above joined strings, use the Split() method as shown in the following code −Example Live Demousing System; public class Demo { public static void Main() { string[] str = { "Java", "AngularJS", "Python", "jQuery", "HTML5" }; // join words string res = string.Join(" ", str); Console.WriteLine("Joined Strings... "+res); string[] convert = res.Split(' '); Console.WriteLine("Separate Joined Strings..."); ... Read More
In a bool array, you can store true and false values. To set a bool array, use the new operator −bool[] arr = new bool[5];To add elements in the array −arr[0] = true; arr[1] = true; arr[2] = false; arr[3] = true; arr[4] = true;Let us see the complete code −Example Live Demousing System; public class Demo { public static void Main() { bool[] arr = new bool[5]; arr[0] = true; arr[1] = true; arr[2] = false; arr[3] = true; arr[4] = true; Console.WriteLine("Displaying values..."); foreach (bool res in arr) { Console.WriteLine(res); } } }OutputDisplaying values... True True False True True
If we want to create a view that takes the values from a table based on some particular condition(s) then we have to use WHERE clause while creating the view. The values depending upon the WHERE clause will be stored in view. The syntax of creating a MySQL view with WHERE clause can be as follows −SyntaxCreate View view_name AS Select_statements FROM table WHERE condition(s);ExampleTo illustrate the above concept, we are using the following data from table ‘Student_info’ −mysql> Select * from student_info; +------+---------+------------+------------+ | id | Name | Address | Subject | +------+---------+------------+------------+ | 101 ... Read More
Using the default, you can get the default value of every reference and value type. The expressions set as default are evaluated at compile-time.To get the default for int −default(int);To get the default for long −default(long)Let us see the code to display default values −Example Live Demousing System; public class Demo { public static void Main() { int val1 = default(int); long val2 = default(long); bool val3 = default(bool); // default for int Console.WriteLine(val1); // default for long Console.WriteLine(val2); // default for bol Console.WriteLine(val3); } }Output0 0 False
Use the default operator to get the default value of StringBuilder.StringBuilder str = default(StringBuilder);Above, we have used the default keywords to get the default value.Let us see the complete code −Example Live Demousing System; using System.Text; public class Demo { public static void Main() { StringBuilder str = default(StringBuilder); Console.WriteLine("Default for StringBuilder = "+str); } }OutputDefault for StringBuilder =The following is the output. It shows a blank space i.e. Null.Default for StringBuilder = Null
Use the default operator to get the default value of bool type −bool a = default(bool);Above, we have used the default keyword to get the default value.Let us see the code to display default value of bool −Example Live Demousing System; public class Demo { public static void Main() { bool a = default(bool); // default for bool Console.WriteLine("Default for bool type = "+a); } }OutputThe following is the output. It shows a blank space i.e. False.Default for bool type = False
MySQL views can be created by using a combination of logical operators like AND, OR, and NOT. It can be illustrated with the help of following examples −Examplemysql> Create or Replace View Info AS select ID, Name, Address , Subject FROM Student_info WHERE (Subject = 'Computers' AND ADDRESS = 'Delhi') OR (Subject = 'History' AND Address = 'Amritsar'); Query OK, 0 rows affected (0.11 sec) mysql> Select * from Info; +------+-------+---------+-----------+ | ID | Name | Address | Subject | +------+-------+---------+-----------+ | 133 | Mohan | Delhi | Computers | +------+-------+---------+-----------+ 1 row in set (0.00 sec)
The nameof operator returns a string literal of an element that can be a variable, type or member.For example, the following is our variable −var vehicle = "motorbike";To get the string literal, use nameof −nameof(vehicle);The following is the code to implement nameof keyword −Example Live Demousing System; public class Program { static void Main() { var vehicle = "motorbike"; Console.WriteLine(nameof(vehicle)); var time = DateTime.Now.ToLocalTime(); Console.WriteLine(nameof(time)); var a = false; Console.WriteLine(nameof(a)); } }Outputvehicle time a