Home - News ( United States | United Kingdom | Italy | Germany ) - Football scores

Showing content from https://docs.microsoft.com/en-us/azure/cosmos-db/postgresql/howto-table-size below:

Determine table size - Azure Cosmos DB for PostgreSQL

APPLIES TO: Azure Cosmos DB for PostgreSQL (powered by the Citus database extension to PostgreSQL)

The usual way to find table sizes in PostgreSQL, pg_total_relation_size, drastically under-reports the size of distributed tables on Azure Cosmos DB for PostgreSQL. All this function does on a cluster is to reveal the size of tables on the coordinator node. In reality, the data in distributed tables lives on the worker nodes (in shards), not on the coordinator. A true measure of distributed table size is obtained as a sum of shard sizes. Azure Cosmos DB for PostgreSQL provides helper functions to query this information.

• Size of actual data in table (the "main fork").
• A relation can be the name of a table or an index.

• citus_relation_size plus:

  • size of free space map
  • size of visibility map

• citus_table_size plus:

  • size of indices

These functions are analogous to three of the standard PostgreSQL object size functions, except if they can't connect to a node, they error out.

Here's how to list the sizes of all distributed tables:

SELECT logicalrelid AS name,
       pg_size_pretty(citus_table_size(logicalrelid)) AS size
  FROM pg_dist_partition;

Output:

┌───────────────┬───────┐
│     name      │ size  │
├───────────────┼───────┤
│ github_users  │ 39 MB │
│ github_events │ 37 MB │
└───────────────┴───────┘

• Learn to scale a cluster to hold more data.
• Distinguish table types in a cluster.
• See other useful diagnostic queries.

RetroSearch is an open source project built by @garambo | Open a GitHub Issue

Search and Browse the WWW like it's 1997 | Search results from DuckDuckGo

HTML: 3.2 | Encoding: UTF-8 | Version: 0.7.4