Techahead Software Architect Interview Questions and Answers

ACID properties are a set of properties that guarantee database transactions are processed reliably.

• Atomicity: Ensures that all operations in a transaction are completed successfully or none at all.

• Consistency: Ensures that the database remains in a consistent state before and after the transaction.

• Isolation: Ensures that the execution of multiple transactions concurrently does not interfere with each other.

• Durability:...read more

To find the mid point of a linked list, use two pointers - one moving at double the speed of the other.

• Initialize two pointers, slow and fast, at the head of the linked list.

• Move the slow pointer by one node and the fast pointer by two nodes until the fast pointer reaches the end of the list.

• The node at which the slow pointer is currently pointing is the mid point of the linked list.

Merge Sort is a divide and conquer algorithm that divides the input array into two halves, sorts them separately, and then merges them.

• Divide the array into two halves recursively

• Sort each half separately

• Merge the sorted halves back together

Foreign key is a field in a relational database table that links to a primary key in another table.

• Ensures referential integrity between tables

• Used to establish relationships between tables

• Prevents orphan records

• Can be used to enforce constraints

Max sum subarray problem involves finding the subarray with the largest sum within an array.

• Iterate through the array and keep track of the current sum and maximum sum seen so far.

• If the current sum becomes negative, reset it to 0 as it won't contribute to the maximum sum.

• Return the maximum sum found.

• Example: For array [-2, 1, -3, 4, -1, 2, 1, -5, 4], the max sum subarray is [4, -1, 2, 1] with sum 6.