SQLGrease vs SQL Diagnostic Manager

Quick verdict

SQLGrease is a SaaS performance monitoring service for SQL Server. A lightweight Windows service (the collector) runs somewhere in your network, gathers and sanitises data from one or more instances, and sends it outbound over HTTPS to a SQLGrease data warehouse, so no inbound firewall ports are needed. Most features need only VIEW SERVER STATE. The vendor lists SQL Server 2008 to 2025, Azure SQL Database, Azure SQL Managed Instance and Amazon RDS. The site names no legal entity, and the most recent dated What's New entry is 31 December 2022 (unsargable predicate recommendations).

Idera SQL Diagnostic Manager (SQL DM) is a self-hosted monitor. Idera describes it as agentless: nothing is installed on the monitored SQL Servers. Its Windows services (which need .NET 4.8 or later) collect data into a SQL Server repository you host (SQL Server 2016 or later, on premises or Amazon RDS Custom for SQL Server), and a browser-based Web Console works on any OS. It covers on-premises SQL Server, Azure SQL Database and Managed Instance, Amazon RDS for SQL Server and Google Cloud, with VMware and Hyper-V metrics alongside. Version 14.3 is current.

Side by side

Key differences

Hosted service versus self-hosted repository

The deepest difference is where the data and the work sit. With SQLGrease you install one Windows service, grant VIEW SERVER STATE, and the vendor stores and serves the history. There is no monitoring server or repository database to size, patch or back up. SQLGrease sanitises query text and plans by default, masking literal parameter values and compile-time values, which reduces what personal data reaches its cloud, but the performance history still lives with the vendor. Some organisations will not allow that, whatever the masking.

With SQL Diagnostic Manager everything runs on your infrastructure: Windows services, a SQL Server 2016 or later repository and the Web Console. Idera's documentation plans for roughly 1 to 3 GB of repository space per monitored instance per year. You own retention, access and backups, and you also own the upkeep. In our view this suits DBA teams with existing Windows and SQL Server operations; SQLGrease suits small teams and consultants who want results without new servers.

Query forensics versus estate-wide monitoring

SQLGrease is built around one question: which query caused this, and when. It keeps per-query waits (it contrasts this with instance-level waits), CPU, IO and duration history at granularities from 1 second up to 1 day, plan history with compile-time parameters for parameter sniffing, lock trees that show what the root blocker was doing, deadlocks grouped by similarity, and tempdb usage. It can map captured plans to Query Store and generate the command to force a plan, which you then run yourself:

-- T-SQL: force a known good plan in Query Store (SQL Server 2016 and later)
EXEC sys.sp_query_store_force_plan @query_id = 48, @plan_id = 49;
-- and to undo it later
EXEC sys.sp_query_store_unforce_plan @query_id = 48, @plan_id = 49;

SQL Diagnostic Manager covers query analysis too (Query Monitor, wait breakdowns, deadlock visualisation, index recommendations that need DBA approval), but its design centre is the whole estate: adaptive baselines that learn each server's normal behaviour, dynamic thresholds, alert actions that run scripts, open ServiceNow tickets, page staff or send SNMP traps, availability group and replication monitoring, hypervisor metrics such as CPU ready and memory ballooning, growth forecasting and, in 14.3, estate-wide enterprise reports and configuration templates.

Vendor activity and what you are buying

Idera is an established vendor with a numbered release line; 14.3 retuned default alert thresholds and modernised the installer. SQLGrease is a smaller operation: the site footer carries a 2026 copyright, but the latest dated What's New entry is 31 December 2022, and the site does not name the company behind it. That does not mean the service is unmaintained, but it is a reason to ask the vendor about the roadmap, support terms (the Support field on the pricing page is blank) and data handling before relying on it for production monitoring.

Pricing models

SQLGrease publishes three plans priced by stored data volume with a recommended CPU range, unlimited users and a floating licence that can move between environments or engagements. Trimming retention helps control which plan you need. What the page does not say is whether a plan covers one server, one instance or several, or which currency the dollar amounts are in. SQL Diagnostic Manager is priced per monitored instance with no per-gigabyte ingest fees, a published starting figure without a stated term, term licences of up to 2,000 days and volume pricing through sales. For a handful of servers the published numbers favour SQLGrease on paper, but confirm the unit with SQLGrease and the term with Idera before comparing totals.

Pricing and licensing

SQLGrease. Listed on sqlgrease.com/Home/Pricing on 7 November 2026, shown with a dollar sign and no currency named: Basic $79 per month or $806 per year (8 GB storage, recommended up to 8 CPUs); Standard $99 per month or $1,010 per year (15 GB, 8 to 24 CPUs); Premium $119 per month or $1,214 per year (30 GB, 24 or more CPUs). All plans have unlimited users. The page does not say whether a plan covers one server or instance. A 30-day trial needs no credit card. A SQLGrease Lite option keeps only 2 hours of history; no price is published for it.

Idera SQL Diagnostic Manager. Listed on Idera's product page on 7 November 2026: "Starting at $1,247 per instance", with no currency code and no stated term, no per-gigabyte ingest fees, volume pricing from sales and, per the FAQ, term licensing of up to 2,000 days. A 14-day full-feature trial is available without a credit card. Ask Idera for a quote that states the term and currency.

Pricing checked on the vendors' official pages on 7 November 2026. Prices change; confirm before buying.

Where each one leads

Limitations

When to choose each

When neither is right

• You also monitor PostgreSQL, MySQL or Oracle: see database monitoring tools and Datadog vs SolarWinds DPA.
• You want other self-hosted SQL Server monitors to shortlist: compare Redgate Monitor vs SQL Sentry and SQL Sentry vs SolarWinds DPA.
• You only need plan history and regression fixes for a few databases: built-in Query Store may be enough, at no extra cost.

Final recommendation

Frequently asked questions

Sources

• SQLGrease home page
• SQLGrease features
• SQLGrease pricing
• SQLGrease pricing options (trial and Lite)
• SQLGrease what's new
• Idera SQL Diagnostic Manager product page
• SQL Diagnostic Manager 14.3 requirements
• SQL Diagnostic Manager 14.3 announcement

Checked November 2026.

How we research comparisons: our editorial method.