Powershell searching many strings at once with a loop

Question

The purpose of the script below is to search for a given string in a particular folder. The script does not error. But the results are not correct.

If the search is done individually search for one string it works. Once the script is run in a loop if the string is found in at least 1 file I get the correct output of files containing that string.

The issue is when the code is run in a loop and the string does not appear in any file the script returns a bunch of files where the string does not exists. If I run string individually i get no results which is correct.

I set FileOut = $null in the event that maybe this variable just needed to be cleared before setting but still same issue

$a = Get-Date
write-Host $a

$SearchStrings = Get-Content "C:\Users\Someuser\Desktop\DataDumps_PS\Delete_input_2.txt"

$out_file = "C:\Users\Someuser\Desktop\DataDumps_PS\Delete5_$(get-date -f yyyyMMdd).txt"

$RootString = "E:\SSIS_packages\"

Foreach($SearchString in $SearchStrings){

Write-host $SearchString

$FileOut = $null
                                        
$FileOut = Get-ChildItem $RootString -recurse | Select-String -pattern $SearchString | group 
path | Select-Object name,@{name="SearchString"; expression={ 
$SearchString.replace('[','').replace(']','')} } 

$FileOut | Out-file -width 300 -filepath $out_file -append
}

Sameple output with loop this string "DELETE FROM dbo.PRE_GPS_Upload_Status" returns below output. Which is wrong

Name                                                                                  SearchString                          
----                                                                                  ------------                          
E:\SSIS_packages\ENRL_ETL\EWQ_APP\File_Extract_GPS_Fallouts.dtsx                   DELETE FROM  dbo.PRE_GPS_Upload_Status
E:\SSIS_packages\ENRL_ETL\SNP_YearlyVerification\File_Resub_Req_File_Extract.dtsx DELETE FROM  dbo.PRE_GPS_Upload_Status
E:\SSIS_packages\ETL_PNDT\File_GPS_Data_Pull.dtsx                                 DELETE FROM  dbo.PRE_GPS_Upload_Status
E:\SSIS_packages\ETL_PNDT\File_GPS_Data_Pull_06072021.dtsx                        DELETE FROM  dbo.PRE_GPS_Upload_Status
E:\SSIS_packages\ETL_PNDT\File_GPS_Data_Pull_09092019.dtsx                        DELETE FROM  dbo.PRE_GPS_Upload_Status
E:\SSIS_packages\ETL_PNDT\File_GPS_Data_Pull_09232021.dtsx                        DELETE FROM  dbo.PRE_GPS_Upload_Status
E:\SSIS_packages\ETL_PNDT\File_GPS_Data_Pull_11162020.dtsx                        DELETE FROM  dbo.PRE_GPS_Upload_Status
E:\SSIS_packages\ETL_PNDT\Backup\File_GPS_Data_Pull_06.03.2019.dtsx               DELETE FROM  dbo.PRE_GPS_Upload_Status
E:\SSIS_packages\ETL_PNDT\Backup\File_GPS_Data_Pull_4.2.2019.dtsx                 DELETE FROM  dbo.PRE_GPS_Upload_Status
E:\SSIS_packages\ETL_PNDT\Backup_10112019\File_GPS_Data_Pull_10112019.dtsx        DELETE FROM  dbo.PRE_GPS_Upload_Status

Sample output searching only 1 string (this is correct output)

Name                                                                                  SearchString                          
----                                                                                  ------------

Any thoughts on this behavior?

score 2 · Accepted Answer · answered Oct 01 '21 at 17:53

2

Your Select-String -pattern $SearchString is likely to blame. Because -pattern uses regular expressions to do its matching, it's probably seeing those braces [ ], and matching on something in the file. Try swapping out -pattern for -SimpleMatch.

answered Oct 01 '21 at 17:53

Seb

179
2
6

Wow I cant believe it was that simple. Yes that was the answer 100%. I am getting back correct results. How does the pattern parameter act differently in a loop. With out loop I was getting the correct answer with pattern? Thank you! – Leo Torres Oct 01 '21 at 18:23
@LeoTorres - also, you may find that using the `-Path` parameter of `Select-String` is faster than using `Get-ChildItem`. it usually is MUCH faster ... [*grin*] – Lee_Dailey Oct 01 '21 at 19:51
@Seb: Nice deduction, but note that `-SimpleMatch` is a _switch_ that you pass _in addition to_ `-Pattern` (which can be bound positionally), not instead of it. – mklement0 Oct 02 '21 at 19:06
@LeoTorres, the parameter wouldn't act differently in a loop; perhaps only some of your search strings contain `[` and `]`. Also note that `Select-String` accepts _multiple_ patterns (an array of patterns), any of which can trigger a match. – mklement0 Oct 02 '21 at 19:09

Powershell searching many strings at once with a loop

1 Answers1