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Why Your Database POC Results Are Unreliable: 3 Common Mistakes

A database POC is supposed to reduce uncertainty.

But a poorly designed POC can do the opposite: it can produce a very confident answer that is completely wrong.

This is especially important when evaluating GBase Database, or any database platform for a production migration.

After looking at database selection and migration projects, three POC mistakes appear again and again:

  1. Testing with too little data
  2. Testing single queries without concurrency
  3. Ignoring the operational toolchain

If any of these are missing, your GBase Database POC is probably measuring the lab — not your production workload.


1. The Data Volume Is Too Small

A database can look extremely fast when the dataset is tiny.

Testing an analytical workload with 10,000 or 100,000 rows tells you very little about how the system will behave with hundreds of millions or billions of rows.

This is particularly important when evaluating analytical databases such as GBase Database(GBase 8a MPP Cluster).

Columnar storage, compression, partitioning, indexing strategies, and MPP parallelism often become much more meaningful as data volume increases.

A small dataset can hide the real behavior of an analytical database.

Better approach: test near-production scale

Your POC dataset should be large enough to expose the behavior you care about.

At minimum, consider:

  • realistic table sizes
  • realistic data distribution
  • realistic data skew
  • representative historical data
  • production-like indexes and partitions

Ideally, test with a dataset close to production scale.

If production has 500 million rows, a 10,000-row POC is not a smaller version of production.

It is a different workload.

For a GBase Database POC, the objective should be to reproduce the data characteristics that will actually affect query execution, storage, compression, and resource consumption.


2. You Test Queries, But Not Concurrency

A query that takes 200 ms when executed once may behave very differently when hundreds of sessions execute similar workloads simultaneously.

Single-query testing hides problems such as:

  • lock contention
  • connection pool saturation
  • CPU competition
  • memory pressure
  • I/O contention
  • resource isolation problems

For example:

-- Representative analytical workload
SELECT
    region,
    SUM(amount) AS revenue
FROM orders
WHERE order_date >= DATE '2026-01-01'
GROUP BY region;
Enter fullscreen mode Exit fullscreen mode

Running this query once answers:

"How fast is this query?"

Running it under realistic concurrency answers a much more useful question:

"How does the database behave when my users actually arrive?"

Better approach: reproduce the workload mix

A realistic GBase Database POC should combine different query types and transaction patterns instead of measuring isolated SQL statements.

Measure more than average latency:

  • throughput
  • P95/P99 latency
  • error rate
  • CPU utilization
  • memory utilization
  • lock or contention events
  • connection pool behavior

The goal is not to find the fastest single query.

The goal is to find the performance boundary of the system.

This matters even more when comparing different GBase Database architectures, because transaction-heavy, analytical, and mixed workloads can stress a database in very different ways.


3. You Ignore the Database Toolchain

This is probably the easiest POC problem to overlook.

A database is not just a query engine.

Production also requires:

  • migration
  • backup and restore
  • monitoring
  • disaster recovery
  • user and permission management
  • operational scripts
  • troubleshooting workflows

A database can perform extremely well in a benchmark and still become a painful production choice if the surrounding toolchain is immature.

Imagine discovering during go-live that:

backup works, but restoring the production dataset takes days to validate.

That is not a performance problem.

It is a POC problem.

Better approach: test operations before production

Put operational tasks inside the POC scope.

At minimum, validate:

  • schema and data migration
  • backup and restore
  • monitoring integration
  • failure recovery
  • operational procedures
  • data consistency checks

For a GBase Database migration POC, compatibility should also be tested at multiple layers:

SQL syntax → interfaces/drivers → migration and operational toolchain

This is one reason GBase Database evaluation should go beyond SQL compatibility.

For example, GBase Database(GBase 8s) targets enterprise transaction workloads, while migration validation also needs to cover the interfaces, tools, HA behavior, and operational procedures surrounding the database.

Compatibility is not just:

"Does this SQL run?"

It is also:

"Can the entire system be operated after migration?"


A Better GBase Database POC Checklist

Before declaring a POC successful, ask three questions.

1. Did we test realistic data volume?

If the answer is no, your performance numbers are probably optimistic.

2. Did we test realistic concurrency?

If the answer is no, your latency numbers are probably incomplete.

3. Did we test the operational toolchain?

If the answer is no, your production readiness is still unknown.

A useful GBase Database POC should therefore cover three dimensions:

Real data × Real concurrency × Real operations

Not just:

SQL benchmark × Single query × Happy path


The Real Purpose of a GBase Database POC

A database POC is not designed to prove that a database is powerful.

It is designed to answer a much harder question:

Can this database run my workload reliably in production?

For GBase Database, that means testing the workload you actually have, at a scale that matters, under pressure that resembles production, with the operational processes required after go-live.

The same principle applies whether you are evaluating GBase Database(GBase 8s) for transaction-heavy workloads, GBase Database(GBase 8a MPP Cluster) for analytical workloads, or GBase Database(GBase 8c) for distributed and mixed workloads.

The POC should validate the workload fit, not simply demonstrate product features.

TIL takeaway:

A POC that doesn't reproduce your data volume, concurrency, and operational workflow isn't really validating GBase Database.

It's validating the test environment.

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