Question 1

What exactly is Quentra?

Accepted Answer

A software layer between your application and SQL Server: queries reach SQL Server through Quentra.

It sees and measures every one of them and, based on rules you enable, rewrites them, answers them from cache, or blocks them. Live monitoring comes from the same vantage point. Nothing is installed on SQL Server: no agents, no triggers, no objects.

Question 2

Is Quentra a monitoring tool or a security product?

Accepted Answer

Both; the same software does three jobs:

- Performance: it watches your queries, proposes fixes for problematic ones, and advises on indexes and stored procedures
- Security: it blocks SQL injection and brute force, masks sensitive data, and keeps an audit trail
- Visibility: live monitoring, server health, and change tracking

Which one leads depends on what you need.

Question 3

Does it replace SQL Server's own Query Optimizer?

Accepted Answer

No. The optimizer keeps doing its job.

Quentra fixes the query shapes that prevent the optimizer from producing a good plan (columns wrapped in functions, implicit type conversions, LIKE '%x', unnecessary DISTINCT) before the query reaches SQL Server. The optimizer then finds the good plan for the corrected text on its own.

Question 4

What size of system is it suited for?

Accepted Answer

It scales from a single small server to enterprise environments running multiple Quentra servers.

Quentra inspects queries as they flow; it doesn't buffer their contents in memory. In load tests, a single Quentra server has handled up to 15,000 queries per second without issue. In larger environments, Quentra can be installed per application server (Pro / Enterprise).

Question 5

Do I need to change my application?

Accepted Answer

No code changes. You only point the server address in your connection string at Quentra (e.g. quentra-host,14330).

Question 6

Does it work with our ERP or off-the-shelf software?

Accepted Answer

Yes. Quentra sees queries on the network, so it doesn't need the software's source code.

The unchangeable queries of packaged software you can't modify are exactly what Quentra is built for.

Question 7

Do queries from SSMS and reporting tools go through Quentra too?

Accepted Answer

Any client that uses Quentra as its server does: SSMS, Power BI, Excel, Reporting Services, sqlcmd, and so on. Clients that connect straight to SQL Server bypass it.

The Connections tab in Live Monitor shows which sessions come through Quentra and which connect directly.

Question 8

Will Quentra change my existing queries? When, and under what conditions?

Accepted Answer

Only through rules you enable. Before a query can ever be rewritten, it has to pass every one of these checks:

1. Does it match a known problem?
2. Are the conditions right? (is the needed index there, are the settings suitable)
3. Does the rewritten version return the same results?
4. Is it actually faster? (measured, never assumed)
5. Only then is a suggestion created, not a change.

Suggestions are report-only at first and never touch your queries. Enabling a rule is your decision, and every rule can be switched off with one click.

Question 9

What happens if I want to remove Quentra?

Accepted Answer

Point your connection string back at the original server; that's it.

There's nothing of Quentra inside SQL Server, and your code never changed, so rollback is instant and complete. The monitoring data lives in Quentra's own files; keep it, export it, or delete it as you wish.

Question 10

Could a bad rewrite change my query's results?

Accepted Answer

Every fix carries an equivalence check: if it can't be proven that the two queries return identical results (say, case sensitivity or a type conversion is ambiguous), no rewrite is generated at all.

Generated rewrites are validated with comparative measurement; once a rule is live, every application of it is logged and can be switched off with one click. Doubtful cases are never decided for you; they're left to you.

Question 11

Does Quentra add latency?

Accepted Answer

Traffic flows through at the packet level, so the added latency is typically a few milliseconds, lost inside the network round trip. Rule matching itself takes microseconds.

With caching enabled, latency doesn't go up; it drops: a repeated query is answered without ever reaching the database.

Question 12

If Quentra goes down, does my application keep working?

Accepted Answer

If the service stops, connections to that address fail, which is why Quentra runs as a monitored Windows service that restarts automatically.

If your license expires, traffic is not cut off: Quentra passes queries straight through without processing them. For high availability we recommend multiple Quentra servers behind DNS/VIP routing.

Question 13

Does Quentra write anything to my database?

Accepted Answer

No. Monitoring data, rules, and events live in Quentra's own store.

Changes the advisor proposes, such as an index, are applied only when you click Run, and only after a two-step confirmation.

Question 14

How do you measure the gains? Can I trust the numbers?

Accepted Answer

Gains are measured, not estimated: the difference in real execution time and reads before and after a rule, multiplied by how often the query actually runs.

Index gains are computed from the server's own execution counters. If a query can't be measured, no number is shown, and the coverage of the measurement is displayed alongside it. You can always cross-check the figures against your server's own data.

Question 15

Does our data leave the company?

Accepted Answer

Query traffic and monitoring data stay on your own server; there is no cloud service receiving your data.

Two exceptions only: the optional AI features and license checks, which transmit nothing but the license identity.

Question 16

Are my queries sent to an AI?

Accepted Answer

Only if you use the AI features, and only to the provider you choose. There are three options:

- Quentra's own hosted service
- A model running entirely inside your network (Ollama, vLLM, and the like)
- AI switched off completely, in which case the rule engine works on its own and no query ever leaves your network

You're asked to make this choice explicitly during setup. The quota applies only to Quentra's hosted AI service; with your own model or API key there is no quota.

Question 17

Does Quentra store my database passwords?

Accepted Answer

Application passwords are not stored; credentials pass through Quentra from client to SQL Server but are never recorded.

Quentra does use its own monitoring account; our recommendation is a dedicated login with monitoring permission only (VIEW SERVER STATE).

Question 18

How secure is Quentra's own admin interface?

Accepted Answer

The interface is password-protected; API endpoints use keys; Enterprise adds role-based access control and SSO.

We recommend exposing the admin port to your management network only. Changing the default password is a mandatory setup step, and the interface goes through regular penetration testing.

Question 19

Is traffic through Quentra encrypted?

Accepted Answer

Yes, TLS on both legs: client to Quentra, and Quentra to SQL Server.

For the rules to work, traffic is decrypted in the middle and re-encrypted; the certificate presented to clients is generated at setup and can be replaced with your organization's own. A separate setting covers the TLS limitations of older SQL Server versions.

Question 20

How does data masking work?

Accepted Answer

Masking happens on the response path, as results return to the client: the data in your database never changes, and the application never notices.

Rules are defined per column and table, and can be combined with application, user, and machine filters ("everyone sees national IDs masked except the accounting app"). Indirect access routes (CAST, views, FOR JSON) are covered too. Data Sentinel discovers sensitive columns on its own and proposes a masking rule for them.

Question 21

Which SQL Server versions are supported?

Accepted Answer

SQL Server 2012 and later (2014, 2016, 2017, 2019, 2022); Express, Standard and Enterprise.

Some advisor features draw on data available in newer versions; on older ones, a slower fallback path is used.

Question 22

Does it work with Azure SQL or cloud databases?

Accepted Answer

It's compatible with Azure SQL Database.

Question 23

Do I need to install an agent or extension on SQL Server?

Accepted Answer

No. Nothing is installed on SQL Server. Quentra is a single Windows service running on a separate machine, or on the same one.

Question 24

How long does setup take, and what does it need?

Accepted Answer

A typical setup takes under 30 minutes: the setup wizard, a monitoring account, and the connection string change.

Requirements: Windows Server, network access to SQL Server, plus disk space and memory for monitoring data. Multiple Quentra instances can run on one machine.

Question 25

Does it work with Always On, clusters, or redundant setups?

Accepted Answer

Yes. Quentra targets the AG listener or cluster name on the back end; on failover it reconnects to the new primary at the same address.

AG status has its own tab in Live Monitor. For read-only routing we recommend a separate Quentra configuration.

Question 26

Can we see our current state before installing anything?

Accepted Answer

Yes. Quentra can run without carrying your traffic at all, using nothing but a read-only monitoring connection: server health, expensive queries, missing indexes, blocking, and the security audit, all visible without touching your connection string.

Question 27

What's the difference between the plans? Which should I pick?

Accepted Answer

- Starter: one Quentra server and one protected SQL Server; monitoring, the rule engine, the AI advisor (standard quota), 7-day retention
- Pro: three Quentra servers; smart cache, central management, 30 days of history, an extended AI quota
- Enterprise: unlimited servers and retention; role-based access, single sign-on (SSO), and offline licensing for air-gapped networks; Data Sentinel can be added

With one SQL Server and one application server, Starter is enough; with several application servers, or if you want caching, go Pro.

Question 28

Can we export our data into our own systems?

Accepted Answer

Yes. Monitoring data is kept in an open format; you can write your own queries in the report designer and export them, and pull data as JSON over the API.

The data sits on your server; it remains yours even after the contract ends.

Question 29

What exactly counts as a "protected SQL Server"?

Accepted Answer

A protected SQL Server in the pricing table is a single SQL Server target that Quentra sits in front of; licensing documents also call it an "instance". Physical server, VM, or named instance makes no difference. It is counted by the number of protected servers, not by CPU cores.

Question 30

What happens to data once Starter's 7-day retention expires?

Accepted Answer

Logs and telemetry older than 7 days are automatically purged and cannot be recovered after retention expires. For longer retention, see the Pro (30 days) or Enterprise (unlimited) plans.

Question 31

Do the prices include tax?

Accepted Answer

Listed prices exclude tax. For invoicing within Turkey, applicable VAT is added separately at the time of billing.

Question 32

What payment methods and billing periods are available?

Accepted Answer

Monthly and yearly billing are both available; you can compare the two on the pricing page. Contact us for current information on accepted payment methods.

Question 33

What's the refund policy?

Accepted Answer

We review refund requests at info@quentra.dev; each request is evaluated individually against billing history.

Question 34

What does the "Data Sentinel" add-on do?

Accepted Answer

Data Sentinel is a real-time data masking add-on that operates on SQL traffic: it masks sensitive fields (e.g. national ID patterns, card numbers) before they reach query results. Only Enterprise customers can buy it; it is not included in Enterprise and costs +$400/mo on top.

Question 35

What's the difference between support tiers?

Accepted Answer

All three tiers (Standard, Priority, Premium) provide email-based support; priority and scope increase with the plan. Contact us for enterprise SLA needs.

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