1. Index Structure
for
Files

2. Secondary Global Allocation Map
Index Allocation Map (IAM) for table 1
Headers
PFS
Page Free space
GAM
Global Allocation Map
SGAM
Secondary Global Allocation Map
Start of table 1
Index Allocation Map (IAM) for table 2
Start of table 2
Index Allocation Map (IAM) for index 90
Start of index 90

3. Cash 1 2 Write-ahead Log 3 4 5 6 Flushing Database T1 x 5 89 T1 y 15 9
T w
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Clean Pages
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Check Point
MinLSN
Flushing
Dirty pages
Database

4. This is the primary key DeptId Name EmpId
Data File – DeptId is the Clustering key Field
DeptId
Name
EmpId 1
Jack
101
Index File 1
Steve
102 1 1
John
103
This is the primary key 2 1
Nancy
104 3 2
Rose
105 2
Abdul
106 2
Pat
107 3
Melissa
108 3
Joe
109

5. DeptId Name EmpId null pointer null pointer null pointer
Data File – DeptId is the Clustering key Field
DeptId
Name
EmpId 1
Jack
101
Index File 1
Steve
102 1 1
John
103 2 1
Nancy
104 3 1
David
112 2
Rose
105 2
Abdul
106 2
Pat
107
null pointer
null pointer 3
Melissa
108 3
Joe
109
null pointer

6. Example of a B-Tree of order 3
We want to insert the following records into a B-tree of order 3 2
Jack
30,000 80
Steve
32,000 8
John
50,000 71
Nancy
55,000 15
Rose
90,000 63
Abdul
35,000 90
Pat
42,000 55
Kathy
45,000 35
Melissa
38,000 51
Joe
39,000
EmpId
Name
Salary

7. Insert index for record:2
Jack
30,000
Null Pointer
Before
After 2

8. Insert index for record:80
Steve
32,000
Before 2
After 2 80

9. Insert index for record:8
John
50,000
Before 2 80
After 8 2 80

10. Insert index for record:71
Nancy
55,000
Before 8 2 80
After 8 2 71 80

11. Insert index for record:15
Rose
90,000
Before 8 2 71 80
After 8 2 15 80 71

12. Insert index for record:63
Abdul
35,000
Before 8 2 15 80 71
After 8 2 15 80 71 63

13. Insert index for record:90
Pat
42,000
Before 8 2 15 80 71 63
After 8 2 15 80 71 63 90

14. Insert index for record:55
Kathy
45,000
Before 8 2 15 80 71 63 90
After 55 8 71 15 63 80 90 2

15. Insert index for record:35
Melissa
38,000 55 8 71 15 63 80 90 2
Before
After 55 8 71 15 63 80 90 2 35

16. Insert index for record:51
Joe
39,000 55
Before 8 71 2 15 35 63 80 90 55 8 71 15 63 2 80 90 51 35
After

17. EmpId Name Salary 2 Jack 30,000 80 Steve 32,000 8 John 50,000 71 Nancy
55,000 15
Rose
90,000 63
Abdul
35,000 90
Pat
42,000 55
Kathy
45,000 35
Melissa
38,000 51
Joe
39,000
EmpId
Name
Salary 55 8 71 15 63 2 80 90 51 35