Online Table Diff

Getting Started

KS DB Merge online Table Diff is a tool designed to compare database tables and query results. Simply paste query results from your database client (SSMS, DBeaver, pgAdmin, etc.) and get the diff result in terms of database table rows identified by their primary key column values. Table columns are automatically mapped by name or by column number. One or more column pairs can be selected as a key. Input tables can also be uploaded as files in CSV format.

Click Open Demo to see how it works:

Here:

• 1Compared tables
• 2ID column is auto-identified as a key. When you paste a new table, the application automatically checks if the first column values are unique and can be used as an ID (the most common case). Otherwise, keys should be configured separately using common toolbar button (see Common Toolbar below). If no keys are specified, the application shows a 'No keys' warning in the 8warning area, and rows are compared by row number.
• 3Changed row, meaning it has the same ID but changed other columns. Changed values are emphasized (e.g., Bob vs. Robert for ID = 4).
• 4New row, meaning this ID does not exist on the other side
• 5total row counts for each table
• 6Per-table toolbar to open table and clear data
• 7Common toolbar to set up key mapping, filter all/new/changed, and other options
• 8Not presented in the demo, but the space on the left of the toolbar contains warnings like this: 'No keys' is described in 2. 'T1/T2 truncated' means not all the data was used from the clipboard or file (see Limitations below):

Per-Table Toolbar

Paste from clipboard to the specified panel. The values delimiter (tab, comma, or semicolon) is auto-detected, and the first row is considered a header with column names.

Paste from clipboard with settings - opens the Data format settings popup to configure the Paste action. In that popup, you can explicitly specify the delimiter and other options and preview the first rows of the parse result (see Data format settings popup below).

Open CSV file to the specified panel. Also opens the Data format settings popup to configure file reading.

Clear table - clears data in the specified panel.

Common Toolbar

Help - opens this Help popup.

Show all, only new and changed, only new, or only changed rows - filter rows to show only required change type.

Column mapping - opens Column mapping configuration (see Column Mapping Popup below).

Open one or two CSV files - allows opening two CSV files at once, showing Data format settings for the first file and then for the second one. This is the same as opening these files one by one.

Clear both tables - clears data in both panels.

Data Format Settings Popup

Preview - first 5 rows of the result.
Delimiter - column values delimiter (tab, comma, or semicolon).
First row is a header - if not, columns are named as Column 1, Column 2, etc.
Skip empty lines - skip lines having no content.
Skip comments - skip lines starting with # or //.

Column Mapping Popup

The difference between Map by Name and Map by Number can be demonstrated by the following example. If we have columns A, B, D on the left and A, C, D on the right, then:

• Map by Name maps A to A, D to D. B on the left and C on the right are not mapped because of the different column name.
• Map by Number maps A to A, B to C (they are both column #2), and D to D.

Mapping type Key values are validated for being unique when clicking OK. If they are not unique, a warning text appears with the first found duplicate value, and mapping cannot be applied in this case.
Mapping type None cannot be changed for non-mapped columns.

Limitations

To keep the UI responsive, the application truncates tables having more than 10,000 values. For example, a table with 99 columns and 200 rows will only load 101 rows (101*99 = 9,999). The 102nd row and others are not loaded because it is above our limit of 10,000 values.

The table does not show text longer than 50 characters, but the whole text value is still compared and highlighted if changed. If you hover over such a cell, you will see the whole cell value in the tooltip, but it may still be truncated due to browser tooltip limitations.

If you compare data copied from a database client, you may also check our desktop tools for MySQL and MariaDB, SQL Server, PostgreSQL, Oracle, SQLite, MS Access, and for databases of different types, for example MySQL vs PostgreSQL (Cross-DBMS). They connect to both databases and do not have these limitations: they compare large tables, many tables at once, and the table structure, show the differences from row counts down to a single changed value, and create a script to synchronize the schema and data. Free versions are available.

Privacy Notice

Table comparison is performed on the server side; however, your data stays in your browser. Our server receives just some numbers associated with table row values. For example, if you compare a row:

FirstName=John, LastName=Doe

versus

FirstName=John, LastName=Smith

our server-side receives values 0, 1, and 2 instead of 'John', 'Doe', and 'Smith'.