How to find the size of a table in SQL?

Piercing the veil: SQL Server

In SQL Server Management Studio (SSMS), you can access storage details through these simple steps:

• Right-click the table in your Object Explorer
• Select Properties
• Navigate to the Storage section.

Or you can dive into the system views for comprehensive details:

SELECT t.name AS 'Table Name',
  p.rows AS 'Row Counts', -- counting sheep is easier, #justsaying
  SUM(a.total_pages) * 8 AS 'Total Space KB', 
  SUM(a.used_pages) * 8 AS 'Used Space KB', 
  (SUM(a.total_pages) - SUM(a.used_pages)) * 8 AS 'Unused Space KB'
FROM 
    sys.tables t
    JOIN sys.indexes i ON t.OBJECT_ID = i.object_id
    JOIN sys.partitions p ON i.object_id = p.OBJECT_ID AND i.index_id = p.index_id
    JOIN sys.allocation_units a ON p.partition_id = a.container_id
GROUP BY 
    t.Name, p.Rows
ORDER BY 
    'Total Space KB' DESC;


Now you can play Sherlock in your database world.

Navigating Oracle's labyrinth

For Oracle, be mindful of different norms:

SELECT segment_name AS "Table", 
  ROUND(SUM(bytes) / 1048576, 2) AS "Size in MB"
FROM dba_segments
WHERE segment_type = 'TABLE' AND segment_name = 'YOURTABLE'
GROUP BY segment_name;


Look for Oracle-specific approaches in their documentation or discussions among community.

Conquering Sybase efficiently

In Sybase, you can use similar command as SQL Server to find the space consumed by a table:

sp_spaceused 'YourTable';


So, talk about consistent user experience!

Data or indexes? Why not both?

Incorporate both data and indexes when determining the authentic size of your table:

SELECT SUM(size) * 8 / 1024 AS 'Size in MB'
FROM sys.master_files
WHERE type_desc = 'ROWS';
-- If Spiderman is 'spider-man', why isn't Batman 'batindex-man'? #pondering


Row, row, row your table

In SQL, row count is maintained separately. Don't forget to include it:

SELECT table_name, 
  table_rows
FROM information_schema.TABLES 
WHERE table_schema = 'your_database';


Also, be aware that COUNT(*) could be a performance hog. It sometimes behaves like a snorlax blocking your database path!

Prettify size representation

For user-friendly analysis, convert table sizes to GB and give anew column name:

SELECT table_name, 
  ROUND(SUM(data_length + index_length) / 1024 / 1024 / 1024, 2) AS 'Size in GB'
FROM information_schema.TABLES 
WHERE table_schema = 'your_database'
GROUP BY table_name;


Now your sizes are more relatable, just like your favorite sitcom!

Stay vigilant: Monitoring and capacity planning

Setting up regular monitoring of your table sizes is crucial for optimizing database performance and efficient capacity planning. It's like taking your database on regular check-ups. Remember, prevention is better than cure!

Power of ordering and large databases

Let's make our analysis even more visual by appending row count and ordering results:

SELECT table_name, 
  ROUND(SUM(data_length + index_length) / 1024 / 1024, 2) AS 'Size in MB',
  table_rows
FROM information_schema.TABLES 
WHERE table_schema = 'your_database'
GROUP BY table_name
ORDER BY table_rows DESC, 'Size in MB' DESC;


This is like ranking your favorite movies by genre and box office returns. In large databases, run these operations during idle times or use batch operations for better performance.

Proactive system design and automated tools

Partitioning and archiving strategies when designing the database can make your size query tasks faster and easier, just like prepping your meal for the week!

Lastly, setting up tracking tools or scripts for log changes, or even setting up alerts, could be your knight in shining armor!