How to Run a Very Large SQL Script Without Opening It in SSMS

Sometimes, you get a SQL script file so large that SQL Server Management Studio (SSMS) or regular text editors can't even open it.
This can happen when the file is hundreds of MBs or even several GBs, often containing bulk data inserts, schema creation, or migration scripts.

In this article, I’ll show you why this happens, and how you can run such scripts without loading them into memory.

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Why SSMS and Notepad Fail

• SSMS tries to load the entire file into memory before executing it.

• Editors like Notepad or even Notepad++ will either crash or freeze if the file is too large.

• Large files (1GB+) consume a lot of RAM during parsing, making it impossible to edit or even view them on normal machines.

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Better Ways to Handle Large SQL Scripts

1. Use sqlcmd to Run the File Directly

sqlcmd is a command-line utility provided by SQL Server that can execute SQL files without loading them fully into an editor.

Example:

sqlcmd -S .\SQL2022 -d master -i "C:\Path\To\BigScript.sql"

Explanation:

• -S .\SQL2022 → Connect to the local SQL Server instance named SQL2022.

• -d master → Start execution in the master database (safe choice for scripts that create databases).

• -i → Path to your SQL file.

If you use SQL authentication:

sqlcmd -S .\SQL2022 -U sa -P YourPassword -d master -i "C:\Path\To\BigScript.sql"

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2. Store the Output in a Log File

You can save execution results for later review:

sqlcmd -S .\SQL2022 -d master -i "C:\Path\To\BigScript.sql" -o "C:\Path\ExecutionLog.txt"

Now you have a clean record of what happened during the execution.

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3. Split the File into Smaller Parts

If you need to edit the script:

• Use tools like GSplit, EmEditor, or a PowerShell script to break the file into smaller chunks.

• Example PowerShell:

Get-Content "C:\Path\BigScript.sql" -ReadCount 1000 | % {
    $i++
    $_ | Out-File "C:\Path\Part_$i.sql"
}

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4. Use a Large File-Friendly Editor

If viewing or editing is absolutely necessary:

• EmEditor

• UltraEdit

• Glogg (view only)

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Final Thoughts

When dealing with massive SQL scripts, the goal is execution without full loading.
The sqlcmd tool is perfect for this job — lightweight, fast, and does not require opening the file in SSMS.

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#SQLServer #DatabaseTips #DevOps #BigData #sqlcmd #Performance

I’m Morteza Jangjoo and “Explaining things I wish someone had explained to me”