How to use a blank password with SQLCMD

Question : I'm trying to execute a stored procedure SQLCMD which requires the use  SQL Authentication Login Method.
I know that there shouldn't be a blank password, but in this test case we are attempting to run the SQLCMD program with a SQL Login but no password.

Don't ask why , it's some legacy code workaround concocted by the application team.

sqlcmd -S SERVER1\myinstance  -d mydb -U user1 -P  -s, -Q "EXEC dbo.mysp value1,value2"

This returns with the following Error message

Sqlcmd: '-P': Missing argument. Enter '-?' for help.

I've tried running without the -P switch and this gives me a password prompt. I've also tried setting the SQLCMDPASSWORD session environment variable and I still getting the Missing argument response.

Is there a way around this problem or are blank passwords not supported through SQLCMD using the SQL Authentication mode?

Answer: Blank passwords are supported using SQLCMD and SQL Authentication.  This all comes with the

standard warning about enforcing password policies etc and security policies.

The way to utilise a blanl password is to use double quotes ("").

In the example you've presented use :

sqlcmd -S SERVER1\myinstance  -d mydb -U user1 -P ""  -s, -Q "EXEC dbo.mysp value1,value2"

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