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Evenly Distribute Customers with Hash Partitions


Creating Partitions for a Hash-Partitioned Table

Write a PostgreSQL query to create two hash partitions for the Customers table.

Solution:

-- Create two hash partitions for the Customers table.
-- Create a partition of the Customers table named Customers_Part1.
CREATE TABLE Customers_Part1 PARTITION OF Customers
-- Define the hash partition with modulus 2 and remainder 0.
FOR VALUES WITH (MODULUS 2, REMAINDER 0);
-- Create a partition of the Customers table named Customers_Part2.
CREATE TABLE Customers_Part2 PARTITION OF Customers
-- Define the hash partition with modulus 2 and remainder 1.
FOR VALUES WITH (MODULUS 2, REMAINDER 1);

Explanation:

  • Purpose of the Query:
    • Distributes customer data evenly across two partitions.
  • Key Components:
    • MODULUS and REMAINDER: Determines how rows are assigned to partitions.
  • Real-World Application:
    • Used in high-traffic applications where even data distribution is crucial.

Notes:

  • More partitions can be added for better load balancing.

For more Practice: Solve these Related Problems:

  • Write a PostgreSQL query to create three hash partitions for a Customers table using MODULUS 3.
  • Write a PostgreSQL query to create a partitioned table for users and divide the data into 4 hash partitions.
  • Write a PostgreSQL query to create hash partitions for a Log table using a modulus of 5 with appropriate remainder values.
  • Write a PostgreSQL query to create hash partitions for a Payments table by specifying modulus and remainder values to form 3 partitions.


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Previous PostgreSQL Exercise: Creating a Hash-Partitioned Table.

Next PostgreSQL Exercise: Inserting Data into a Partitioned Table.

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