One Commit at a Time ! Series - 21

JAVA

public class Main {
  public static void main(String[] args) {
    double myDouble = 9.78d;
    int myInt = (int) myDouble; // Explicit casting: double to int

    System.out.println(myDouble);
    System.out.println(myInt);
  }
}

Explanation :

This Java program demonstrates type casting, specifically converting a double (a floating-point decimal number) into an int (a whole number) using explicit casting.

Here is a step-by-step breakdown:

1. double myDouble = 9.78d;

2. Declares a variable named myDouble of type double and assigns it the value 9.78. The d suffix explicitly denotes a double literal (though it is optional in Java).

3. int myInt = (int) myDouble;

4. Performs explicit casting (also known as narrowing conversion). Because a double can hold decimals and an int cannot, Java requires you to explicitly tell it to convert the type by putting (int) in front of the variable.

5. Crucial detail: When casting a floating-point number to an integer, Java truncates the decimal part entirely—it does not round up. Therefore, 9.78 becomes 9.

6. System.out.println(myDouble);

7. Prints the original double value to the console: 9.78.

8. System.out.println(myInt);

9. Prints the converted integer value to the console: 9.

Output

9.78
9

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SQL

Text Fields vs. Numeric Fields
SQL requires single quotes around text values (most database systems will also allow double quotes).

However, numeric fields should not be enclosed in quotes:

Example

SELECT * FROM Customers
WHERE CustomerID = 1;

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References

https://www.w3schools.com/sql/sql_where.asp
https://www.w3schools.com/java/java_examples.asp