A. Hypothesis can be tested and proven.
Answer is given below
Explanation:
differences between a file-processing system and a database management system is given below
file-processing system
- File system is a software that manages and organizes the files in a storage medium within a computer.
- It doesn’t provide backup and recovery of data if it is lost.
- There is less data consistency in file system.
- File systems provide less security in comparison to DBMS.
- It is less complex as compared to DBMS.
database management system
- DBMS is a software for managing the database
- It provides backup and recovery of data even if it is lost.
- DBMS has more security mechanisms as compared to file system
- It has more complexity in handling as compared to file system.
- There is more data consistency because of the process of normalization.
Answer:
A primary key is a special relational database table column (or combination of columns) designated to uniquely identify each table record. A primary key is used as a unique identifier to quickly parse data within the table. A table cannot have more than one primary key.
Primary Key.
Candidate Key.
Alternate Key.
Super Key.
Composite Key.
Foreign Key.
Unique Key.
In the relational model of databases, a primary key is a specific choice of a minimal set of attributes that uniquely specify a tuple in a relation. Informally, a primary key is "which attributes identify a record," and in simple cases constitute a single attribute: a unique ID.
Explanation:
Answer:
The sum of all positive even values in arr
Explanation:
We have an array named arr holding int values
Inside the method mystery:
Two variables s1 and s2 are initialized as 0
A for loop is created iterating through the arr array. Inside the loop:
num is set to the ith position of the arr (num will hold the each value in arr)
Then, we have an if statement that checks if num is greater than 0 (if it is positive number) and if num mod 2 is equal to 0 (if it is an even number). If these conditions are satisfied, num will be added to the s1 (cumulative sum). If num is less than 0 (if it is a negative number), num will be added to the s2 (cumulative sum).
When the loop is done, the value of s1 and s2 is printed.
As you can see, s1 holds the sum of positive even values in the arr
