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How to Work With Tuple in Python

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Tuple in python is one of the streaming datasets. The other streaming datasets are List and Dictionary. Operations that you can perform on it are shown here for your reference. Writing tuple is easy. It has values of comma separated, and enclosed with parenthesis '()'. The values in the tuple are immutable, which means you cannot replace with new values. #1. How to create a tuple Code: my_tuple=(1,2,3,4,5) print(my_tuple) Output: (1, 2, 3, 4, 5) ** Process exited - Return Code: 0 ** Press Enter to exit terminal #2. How to read tuple values Code: print(my_tuple[0]) Output: 1 ** Process exited - Return Code: 0 ** Press Enter to exit terminal #3. How to add two tuples Code: a=(1,6,7,8) c=(3,4,5,6,7,8) d=print(a+c) Output: (1, 6, 7, 8, 3, 4, 5, 6, 7, 8) ** Process exited - Return Code: 0 ** Press Enter to exit terminal #4.  How to count tuple values Here the count is not counting values; count the repetition of a given value. Code: sample=(1, 6, 7, 8, 3, 4, 5, 6, 7, 8) print(sample

Hadoop: How to find which file is healthy

Hadoop provides file system health check utility which is called "fsck". Basically, it checks the health of all the files under a path It also checks the health of all the files under the '/'(root).
  • BIN/HADOOP fsck / - It checks the health of all the files
  • BIN/HADOOP fsck /test/ - It checks the health of files under the path
By default fsck utility cannot do anything for under replicated blocks and over replicated blocks. Hadoop itself heal the blocks.
Healthy file checking ides

 How to find which file is healthy

  • It prints out dot for each healthy file
  • It will print a message for each file, if it is not healthy, also for under replicated blocks, over replicated blocks, mis-replicated blocks, and corrupted blocks.
  • By default fsck utility cannot do anything for under replicated blocks and over replicated blocks. Hadoop itself heal the blocks.

How to delete corrupted blocks

  • BIN/HADOOP fsck -delete block-names
  • It will delete all corrupted blocks
  • BIN/HADOOP fsck -move block-names
  • It will move corrupted blocks to /lost directory
  • Other options we can use with fsck:
    • files
    • blocks
    • locations

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