Three Ways to Retrieve Row Counts for Snowflake Tables and Views
Tags: rowcounts, snowflake, sql, tutorial
Published: 2024-03-01 19:53:09

Determining the number of rows in a table or view is often essential when working with Snowflake. This information can prove valuable for various purposes, such as performance optimization, data analysis, and monitoring. 

In this article, we will explore different approaches to obtain row counts in Snowflake, ranging from simple SQL queries using `COUNT(*)` to leveraging table statistics. We will also highlight essential considerations and provide SQL snippets to ensure correct execution.

## Method 1: COUNT(*)

The most straightforward way to retrieve row counts for both tables and views in Snowflake is by using the COUNT(*) function in SQL. This method provides an accurate count but can be resource-intensive for larger tables and views.

```
SELECT COUNT(*) AS row_count
FROM database.schema.table;
```

_Important note: Replace database, schema, and table with the appropriate identifiers for your Snowflake environment._

## Method 2: Snowflake Metadata Queries

Snowflake metadata views contain information about databases, schemas, tables, and views, but the row counts for views are not stored in these metadata. By querying the appropriate metadata view and filtering on the desired table, we can efficiently obtain row counts of tables, but this method is not applicable to views.

```
SELECT 
  TABLE_CATALOG AS database,
  TABLE_SCHEMA AS schema,
  TABLE_NAME AS table,
  ROW_COUNT AS row_count
FROM 
  SNOWFLAKE.ACCOUNT_USAGE.TABLES
WHERE 
  TABLE_NAME = 'table'
  AND TABLE_SCHEMA = 'schema'
  AND TABLE_CATALOG = 'database';
```

_Important note: Replace database, schema, and table with the correct identifiers for your Snowflake environment. Additionally, ensure your user has the necessary privileges to access the metadata views._

## Method 3: Using Snowflake Information Schema

Similar to metadata views, Snowflake provides an INFORMATION_SCHEMA containing metadata about databases, schemas, tables, and views. However, like the Snowflake metadata views, the row counts for views are not stored here, so this method is also not applicable to views. By querying the appropriate INFORMATION_SCHEMA view and filtering on the desired table, we can effectively obtain row counts of tables.

```
SELECT 
  TABLE_CATALOG AS database,
  TABLE_SCHEMA AS schema,
  TABLE_NAME AS table,
  ROW_COUNT AS row_count
FROM 
  INFORMATION_SCHEMA.TABLES
WHERE 
  TABLE_NAME = 'table'
  AND TABLE_SCHEMA = 'schema'
  AND TABLE_CATALOG = 'database';
```

_Important note: Replace database, schema, and table with the correct identifiers for your Snowflake environment. Ensure your user has the necessary privileges to access the INFORMATION_SCHEMA._

## Final thoughts

Obtaining row counts in Snowflake tables or views is crucial for various use cases. While the COUNT(*) method provides an accurate count, it can be resource-intensive for large tables. Alternatively, leveraging Snowflake metadata queries or INFORMATION_SCHEMA enables efficient row count retrieval. 

However, it's essential to note the necessary privileges required to access metadata views or INFORMATION_SCHEMA. Additionally, table statistics provide approximate row counts and may not always reflect the latest count. Choose the method that best suits your requirements based on table size, desired accuracy, and associated costs in your Snowflake environment.