DBLense Compare — User Guide

Visual schema and data comparison between two SQL Server databases. Generate synchronization scripts automatically with a side-by-side diff viewer.

Getting Started

Double-click DBLenseCompare.exe — no installation required. The interface is divided into source (left) and target (right) connection panels.

Setting Up Source & Target

1. Click Connect on the Source (left) panel
2. Enter your source server details and select the database
3. Click Connect on the Target (right) panel
4. Enter your target server details and select the database

All four authentication modes are supported: Windows, SQL Server, Azure Entra ID (Password), and Azure Entra ID (MFA).

Source and target can be on different servers, different SQL Server versions, or even a mix of on-premises and Azure.

Schema Comparison

Click Compare Schema to analyze structural differences between the two databases. DBLense compares:

Object Types Compared

• Tables — Columns, data types, nullability, defaults, computed columns, identity settings
• Indexes — Clustered, non-clustered, unique, filtered indexes, included columns
• Constraints — Primary keys, foreign keys, check constraints, unique constraints
• Views — Definition, referenced tables
• Stored Procedures — Full procedure body comparison
• Functions — Scalar, table-valued, inline functions
• Triggers — DML and DDL triggers
• Schemas — Schema ownership and permissions

Comparison Results

Objects are categorized as:

• ● Equal — Identical in both databases
• ● Different — Exists in both but has changes
• ● Only in Source — Missing from target
• ● Only in Target — Missing from source

Data Comparison

Compare actual data between matching tables:

1. Select tables to compare (or use Select All)
2. Click Compare Data
3. Results show row-level differences: inserts, updates, and deletes needed to sync

Data comparison uses primary key or unique constraint columns to match rows between databases. Tables without a key column can use all columns for matching.

Visual Diff Viewer

Click any different object to open the side-by-side diff view:

• Left panel = Source definition
• Right panel = Target definition
• Highlighted lines show exact changes
• Green lines = Additions
• Red lines = Deletions
• Yellow lines = Modifications

This makes it easy to visually understand what changed between two environments.

Synchronization Scripts

After comparison, generate T-SQL scripts to synchronize the target database with the source:

1. Select the objects you want to synchronize (checkboxes)
2. Click Generate Script
3. Review the generated T-SQL
4. Copy to clipboard or Save to file
5. Execute in SSMS or your preferred tool

Scripts handle dependency ordering automatically (e.g., tables before foreign keys, schemas before objects).

Filtering & Search

• Object type filter — Show only tables, views, procedures, etc.
• Status filter — Show only Different, Only in Source, Only in Target
• Search — Find objects by name
• Schema filter — Limit comparison to specific schemas (e.g., dbo only)

Typical Workflows

Deploy Development Changes to Staging

1. Connect Dev database as Source, Staging as Target
2. Run Schema Compare
3. Review differences — select only the objects you want to deploy
4. Generate sync script
5. Review and execute on Staging

Audit Production vs. DR

1. Connect Production as Source, DR as Target
2. Run both Schema Compare and Data Compare
3. Verify no drift between environments
4. Generate a report of any differences

Post-Deployment Validation

1. Before deployment: Compare source → target and save results
2. After deployment: Compare again and verify all differences resolved

System Requirements