# Large Snowflake Tables That Are Loaded but Never Read Canonical: https://www.pointfive.co/efficiency-hub/inefficiencies/large-snowflake-tables-that-are-loaded-but-never-read Some Snowflake tables keep receiving data from COPY jobs, Snowpipe, tasks, dbt models or external ELT tools long after anything stopped reading them. By: PointFive Updated: 2026-09-28 [Cloud Efficiency Hub](https://www.pointfive.co/efficiency-hub) The short version Some Snowflake tables keep receiving data from COPY jobs, Snowpipe, tasks, dbt models or external ELT tools long after anything stopped reading them. PointFive Research Cloud cost research at PointFive Snowflake service [Snowflake Tables](https://www.pointfive.co/efficiency-hub/cloud-services/snowflake-tables) Category [Storage](https://www.pointfive.co/efficiency-hub/service-category/storage) Reference CER-0516 Type Excessive Ingestion or Processing ## Explanation Why the waste happens and who it affects. The dashboard, model or export that consumed the table was retired or repointed, but the pipeline feeding it was never switched off. The account keeps paying twice: compute for every load and transformation, and storage for a table that grows with each run. Pipelines are usually owned by data engineering while consumers sit elsewhere, and nobody is notified when the last reader goes away. Snowflake recognizes the pattern directly: its Optimization insights flag large tables that have not been queried in the last week and tables over 100 GB from which data is written but not read. The cost is ongoing rather than one-off, since write activity on permanent tables also keeps generating Time Travel and Fail-safe storage. ## Billing model The pricing dimensions that drive this cost. Load and transform compute Warehouse credits billed per second while COPY, MERGE, INSERT or task statements run, or serverless charges for Snowpipe and serverless tasks Snowpipe ingestion Billed per GB of files loaded, 0.0037 Platform Credits per GB in the Snowflake Service Consumption Table Table storage Flat rate per TB per month by account type and region, covering active data plus Time Travel and Fail-safe history Post-drop retention A dropped permanent table stays billable through its Time Travel retention period and then 7 days of Fail-safe before storage is released ## How to detect 5 checks to find it in your estate. - Open Snowsight Admin \> Cost management \> Account Overview and review the Optimization insights 'Large tables that are never queried' and 'Tables over 100 GB from which data is written but not read', which Snowflake refreshes weekly - For a longer lookback, query SNOWFLAKE.ACCOUNT\_USAGE.ACCESS\_HISTORY (Enterprise Edition or higher) and find tables that appear in OBJECTS\_MODIFIED but not in BASE\_OBJECTS\_ACCESSED or DIRECT\_OBJECTS\_ACCESSED over 30 to 90 days - Size each candidate with SNOWFLAKE.ACCOUNT\_USAGE.TABLE\_STORAGE\_METRICS (ACTIVE\_BYTES, TIME\_TRAVEL\_BYTES, FAILSAFE\_BYTES) to rank by storage at stake - Attribute the write cost by finding the tasks, pipes and service users that load the table in QUERY\_HISTORY, TASK\_HISTORY and PIPE\_USAGE\_HISTORY - Confirm with owners that no consumer outside Snowflake query history depends on the table, such as a share, a replicated secondary or an occasional regulatory export ## How to fix 5 ways to remove the waste. - Stop the feeding pipeline first: suspend the task (ALTER TASK ... SUSPEND), pause the pipe (ALTER PIPE ... SET PIPE\_EXECUTION\_PAUSED = TRUE), or disable the dbt model or ELT job, so compute stops immediately - Drop the table (DROP TABLE) once owners agree; it can be restored with UNDROP during its Time Travel period, and storage is released only after Time Travel and 7 days of Fail-safe - If the data must be kept but not refreshed, keep a final copy and reduce DATA\_RETENTION\_TIME\_IN\_DAYS, or unload it to external cloud storage - For tables that are rebuilt from source on every run, use transient tables, which have no Fail-safe and at most 1 day of Time Travel - Add a recurring review of write-only tables to data governance, using the Optimization insights or an ACCESS\_HISTORY query, and require an owner tag on pipeline targets ## Documentation Vendor references for pricing and configuration. - [Using optimization insights to save docs.snowflake.com](https://docs.snowflake.com/en/user-guide/cost-insights) - [Understanding storage cost docs.snowflake.com](https://docs.snowflake.com/en/user-guide/cost-understanding-data-storage) - [ACCESS\_HISTORY view docs.snowflake.com](https://docs.snowflake.com/en/sql-reference/account-usage/access_history) - [TABLE\_STORAGE\_METRICS view docs.snowflake.com](https://docs.snowflake.com/en/sql-reference/account-usage/table_storage_metrics) - [Snowflake Service Consumption Table snowflake.com](https://www.snowflake.com/legal-files/CreditConsumptionTable.pdf) ## Related inefficiencies [Browse the library](https://www.pointfive.co/efficiency-hub) - Snowflake Tables CER-0126 ### [Retention of Unused Data in Snowflake Table](https://www.pointfive.co/efficiency-hub/inefficiencies/retention-of-unused-data-in-snowflake-table) Retention of stale data occurs when old, no longer needed records are preserved within active Snowflake tables. Without lifecycle policies or regular purging, tables accumulate outdated data. Retaining large volumes of inactive or... Storage - Snowflake Snapshots CER-0111 ### [Excessive Time Travel and Fail-safe Storage from High-Churn Snowflake Tables](https://www.pointfive.co/efficiency-hub/inefficiencies/excessive-snapshot-storage-from-high-churn-snowflake-tables) Snowflake automatically maintains previous versions of data when tables are modified or deleted. For tables with high churn - meaning frequent INSERT, UPDATE, DELETE, or MERGE operations - this can cause a significant buildup of historical... Storage - Azure Managed Disks CER-0338 ### [Underutilized Azure Managed Disk Reservations](https://www.pointfive.co/efficiency-hub/inefficiencies/underutilized-azure-managed-disk-reservations) Azure Managed Disk reservations allow organizations to pre-purchase Premium SSD capacity at a discounted rate by committing to a one-year term. However, these reservations operate on a strict use-it-or-lose-it basis - if reserved disk... Storage --- Source: the public page above. Product screenshots and illustrative interfaces are examples, not live customer data.