Concept explainers
Explanation of Solution
Concurrency control:
The purpose of concurrency control is to ensure the serializability of transaction in a multiuser
Common problems with concurrent transaction execution:
Concurrency transaction is one or more transactions are processed on same time. During the concurrency transaction execution the following problems can occur in the transaction. They are:
- Lost updates
- Uncommitted data
- Inconsistent retrievals
Lost updates:
A data can be lost when the two different transactions want to update same field or row within the database at the same time.
- For example: if the transactions “T1” and “T2” want to update the same element and one of the updates is lost or overwritten by other transactions.
Uncommitted data:
The data of the transactions are not committed when the transactions are executed concurrently...

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Chapter 10 Solutions
EP MINDTAPV2.0 FOR CORONEL/MORRIS'S DAT
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- Good morning, please solve this trying to follow this criteria. (use Keil) Abstract describing the requirements and goals of the assignment. List file with no errors or warnings. Brief description of your implementation design and code. Debugging screen shots for different scenarios with your reference and comments. Conclusion (and please give me the code without errors, make sure it is working)arrow_forwardGood mrng, please solve this trying to follow this criteria. (use Keil) Abstract describing the requirements and goals of the assignment. List file with no errors or warnings. Brief description of your implementation design and code. Debugging screen shots for different scenarios with your reference and comments. Conclusion (and please give me the code without errors, make sure it is working)arrow_forward#include <stdio.h> #include <stdlib.h> #include <unistd.h> int global_var = 42; // int* function(int *a) { int local_var = 10; // *a = *a + local_var; int *local_pointer = (int *)malloc (size of (int) * 64); // Allocated array with 64 integers return local_pinter; } int main() { int local_main[1024*1024*1024*1024*1024] = {0}; // initialize an array and set all items as 0 int *heap_var = (int *)malloc(size of(int) * 16); // Allocated array with 16 integers *heap_var = 100; function(heap_var); printf(“the value is %d\n”, *heap_var); free(heap_var); // release the memory return 0; } 1) draw the memory layout of the created process, which should include text, data, heap and stack [2 marks]. 2) Indicate which section the variables are allocated [2 marks]: global_var local_var, local_pointer local_main heap_var, *heap_var (the data that it points to) 3) Does this code have memory leaking (heap memory is not released)? [2 marks] 4) The…arrow_forward
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