Dagster Data Engineering Glossary:
Data Fragmentation
Data fragmentation definition:
Data fragmentation refers to the breaking down of data into smaller chunks or fragments for storage and management purposes. In modern data engineering, data fragmentation is often used to optimize data processing and storage, as well as to improve data availability and scalability.
Fragmentation can be applied to various types of data, such as files, databases, or objects, and can be done in various ways, such as horizontal fragmentation (splitting data by rows), vertical fragmentation (splitting data by columns), or hybrid fragmentation (a combination of horizontal and vertical fragmentation).
Data fragmentation example using Python:
Please note that you need to have the Pandas library installed in your Python environment to run the following code examples.
Here's a self-contained Python example that demonstrates horizontal fragmentation of a pandas DataFrame:
import pandas as pd
# Create a sample DataFrame with 10 rows and 3 columns
df = pd.DataFrame({'A': [1, 2, 3, 4, 5, 6, 7, 8, 9, 10],
'B': ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j'],
'C': [0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0]})
# Split the DataFrame into two fragments: one with rows 0 to 4 and one with rows 5 to 9
df1 = df.iloc[:5]
df2 = df.iloc[5:]
# Print the original DataFrame and the two fragments
print('Original DataFrame:')
print(df)
print('Fragment 1:')
print(df1)
print('Fragment 2:')
print(df2)
This will yield the following output:
Original DataFrame:
A B C
0 1 a 0.1
1 2 b 0.2
2 3 c 0.3
3 4 d 0.4
4 5 e 0.5
5 6 f 0.6
6 7 g 0.7
7 8 h 0.8
8 9 i 0.9
9 10 j 1.0
Fragment 1:
A B C
0 1 a 0.1
1 2 b 0.2
2 3 c 0.3
3 4 d 0.4
4 5 e 0.5
Fragment 2:
A B C
5 6 f 0.6
6 7 g 0.7
7 8 h 0.8
8 9 i 0.9
9 10 j 1.0
In this example, we create a sample DataFrame with 10 rows and 3 columns. We then split the DataFrame into two fragments using the iloc
method of pandas: df1
contains rows 0 to 4, and df2
contains rows 5 to 9. Finally, we print the original DataFrame and the two fragments to verify that the data has been correctly fragmented. This example demonstrates horizontal fragmentation, as we split the data by rows.
In practice, data fragmentation can be used in a variety of data engineering scenarios, such as distributed computing, parallel processing, or database sharding, to name a few. By breaking down data into smaller, more manageable fragments, we can distribute data processing and storage more efficiently, reduce data access times, and improve overall system performance and scalability.