by default, Get-Content in powershell reading the file as a one long string. which means you might have an issue if you have multiple lines of SQL statements as it will read this

IF EXISTS(SELECT 1 FROM sys.procedures WHERE NAME = ‘PSTest’)
BEGIN
DROP PROCEDURE PsTest
END
GO

becoming

IF EXISTS(SELECT 1 FROM sys.procedures WHERE NAME = ‘PSTest’) BEGIN DROP PROCEDURE PsTest END GO

so how to read multiple lines using Power Shell?

Before Power Shell 3.0 you can use the code snippet below

(Get-Content $FilePath) -join "`r`n" 

Power Shell 3.0 and above, you can use -Raw parameter

Get-Content $FilePath -Raw