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Batch script remove BOM () from file


I have created a batch script to copy SQL files from a folder into one big SQL script. The problem is when I run this one SQL script it comes up with the error

Incorrect syntax near ''

I copied the one SQL script into Notepad++ and set the encoding to ANSI. I see this symbol  (BOM) on the lines where the error is happening.

Is there anyway I can automatically remove this within my batch script. I don't want to keep manually remove this every time I run this task.

Below is the batch script I have currently

@echo off

set "path2work=C:\StoredProcedures"
cd /d "%path2work%"

echo. > C:\FinalScript\AllScripts.sql

for %%a in (*.sql) do (

    echo. >>"C:\FinalScript\AllScripts.sql"
    echo GO >>"C:\FinalScript\AllScripts.sql"
    type "%%a">>"C:\FinalScript\AllScripts.sql"
    echo. >>"C:\FinalScript\AllScripts.sql"
)

Solution

  • This is because the type command will preserve the UTF-8 BOM, so when you combine multiple files which have the BOM, the final file will contain multiple BOMs in various places in middle of the file.

    If you are certain that all the SQL files that you want to combine, start with the BOM, then you can use the following script to remove the BOM from each of them before actually combining them.

    This is done by piping the output of type. The other side of pipe will consume the first 3 bytes (The BOM) with the help of 3 pause commands. each pause will consume one byte. The rest of stream will be send to the findstr command to append it to final script.

    Since the SQL files are encoded UTF-8 and they may contain any characters in the Unicode range, certain code pages will interfere with the operation and may cause the final SQL script to be corrupted.

    So this has been taken into account and the batch file will be restarted with code page 437 which is safe for accessing any binary sequence.

    @echo off
    setlocal DisableDelayedExpansion
    
    
    setlocal EnableDelayedExpansion
    for /F "tokens=*" %%a in ('chcp') do for %%b in (%%a) do set "CP=%%~nb"
    if  !CP! NEQ 437 if !CP! NEQ 65001 chcp 437 >nul && (
    
        REM for file operations, the script must restatred in a new instance.
        "%COMSPEC%" /c "%~f0"
    
        REM Restoring previous code page
        chcp !CP! >nul
        exit /b
    )
    endlocal
    
    
    set "RemoveUTF8BOM=(pause & pause & pause)>nul"
    set "echoNL=echo("
    set "FinalScript=C:\FinalScript\AllScripts.sql"
    
    :: If you want the final script to start with UTF-8 BOM (This is optional)
    :: Create an empty file in NotePad and save it as UTF8-BOM.txt with UTF-8 encoding.
    :: Or Create a file in your HexEditor with this byte sequence: EF BB BF
    :: and save it as UTF8-BOM.txt
    :: The file must be exactly 3 bytes with the above sequence.
    (
        type "UTF8-BOM.txt" 2>nul
    
        REM This assumes that all sql files start with UTF-8 BOM
        REM If not, then they will loose their first 3 otherwise legitimate characters.
        REM Resulting in a final corrupted script.
        for %%A in (*.sql) do (type "%%~A" & %echoNL%)|(%RemoveUTF8BOM% & findstr "^")
    
    )>"%FinalScript%"