Skip to content
METRIC OAK

New: the 3-week Data Platform Assessment: fixed fee, priced roadmap. See what's included →

Migration

Vertica to Snowflake migration: a practical guide

How to migrate Vertica to Snowflake: exporting to Parquet and loading with COPY INTO, replacing projections, flex tables to VARIANT, rewriting TIMESERIES with time spines and ASOF JOIN, UDx and in-database ML.

Hemant Walchale

Hemant Walchale
· 2 min read

Vertica serves many event, telemetry and marketing analytics workloads. Teams move to Snowflake to stop managing nodes, projections and resource pools, and to get elastic compute per workload. Most Vertica SQL converts easily; time-series syntax, flex tables and extensions need deliberate rewrites.

This is the approach we recommend.

1. Inventory

List schemas, tables, projections, flex tables, views, UDx, COPY load jobs, ML models, resource pools, schedules and consumers. query_requests and projection_usage show what is queried. Archive the rest.

2. Map Vertica to Snowflake

Vertica On Snowflake
Tables Snowflake tables
Projections (ORDER BY, SEGMENTED BY) Removed; optional clustering keys
Flex tables VARIANT columns
COPY from files Stages with COPY INTO, Snowpipe
EXPORT TO PARQUET The path for historical data
TIMESERIES, gap filling, interpolation Time spine with GENERATOR, joins, window functions, ASOF JOIN
Analytic functions Window functions
UDx (C++, Java, Python, R) SQL, Python, Java or JavaScript UDFs
In-database ML Snowpark Python, or Cortex ML functions for common forecasting and anomaly tasks
Resource pools Separate virtual warehouses per workload
Roles and grants Role-based access control, masking and row access policies

3. Convert SQL

Most queries convert with small changes. Test date and time functions, INTERVAL arithmetic, string functions, LIMIT ... OVER patterns and implicit casts, then rewrite time-series queries using the patterns above.

4. Move data and reconcile

Export each table to Parquet on cloud storage, load it with COPY INTO, and keep tables in sync from upstream sources during the parallel run. Compare every table by domain; event data needs special care with timestamp precision and time zones.

5. Shrink and retire

Remove Vertica nodes as domains move and stop renewing licence capacity after the final cutover.

The short version

Export to Parquet and load with COPY INTO, drop projections, move flex tables to VARIANT, rewrite TIMESERIES with time spines and ASOF JOIN, convert UDx and ML to Snowflake functions and Snowpark, separate warehouses per workload, reconcile and retire nodes by domain.

Compare with Vertica to Databricks, or browse all migration guides.

Not sure where your own platform stands? Take the free 3-minute data platform scorecard, or see how we work on Snowflake. Unfamiliar terms are explained in the data engineering glossary.

Frequently asked questions

How are Vertica time-series queries converted?

Vertica's TIMESERIES clause with gap filling and interpolation has no single equivalent. Generate a time spine (for example with GENERATOR), join events to it, and use window functions to fill or interpolate. Snowflake's ASOF JOIN is useful for matching each point in time to the latest prior event.

What replaces flex tables?

VARIANT columns. Load semi-structured data as VARIANT, query it with path notation and FLATTEN, and promote frequently used fields to typed columns for performance and clarity.

Do we need anything like projections in Snowflake?

No. Snowflake prunes micro-partitions automatically. For very large tables filtered on the same columns, a clustering key gives a similar benefit to a sorted projection, without maintaining extra copies.

Have 30 minutes? Get a senior architect’s view of your data platform.

No sales deck. You talk to the engineer who would lead the work.

Book an architecture review