Join SQL query Results and Get-ChildItem Results - sql-server

Question

Background: I have a directory with a number of files that are imported to SQL server.
Task: Creating a PowerShell script which will pick up files within this directory and use the filenames as in the SQL query.
Ultimate objective: To display SQL results besides the filenames but the resultset being displayed should also show files having no entries in SQL server. Something like RIGHT JOIN in SQL server queries.
Powershell Code
$files = Get-ChildItem -Recurse -Force $filePath -ErrorAction SilentlyContinue | Where-Object { ($_.PSIsContainer -eq $false) } | Select-Object Name
$Server = "Loadv1"
$DB = "LoadDB"
$dbResults = #()
ForEach ($file in $files)
{
$fileName = $file.name
write-host $fileName
if($fileName.Length -gt 1)
{
$Query = "
SELECT FileName,CurrentStatus
FROM LogStatus
WHERE FileName LIKE '$fileName%'
"
# Write-host $Query
}
$dbResults += Invoke-Sqlcmd -ServerInstance $Server -Database $DB -Query $Query
}
$dispResults = $dbResults,$file
$dispResults | Format-Table -autosize
Work done so far: I have been able to fetch the file names using Get-ChildItem and loop them to get the query results. However, the result I am currently getting does not show the files that don't have corresponding entry in SQL server table
Current Result
OperationalLanding20150622061502.dat
OperationalLandingAudit20150622061502.dat
OperativeThird_Party_System20150616090701.dat
FileName CurrentStatus
OperationalLandingAudit20150622061502.dat SSIS Package Complete
OperativeThird_Party_System20150616090701.dat SSIS Package Complete
Expected Result
OperationalLanding20150622061502.dat
OperationalLandingAudit20150622061502.dat
OperativeThird_Party_System20150616090701.dat
FileName CurrentStatus
OperationalLanding20150622061502.dat NULL
OperationalLandingAudit20150622061502.dat SSIS Package Complete
OperativeThird_Party_System20150616090701.dat SSIS Package Complete
Hoping I was able to explain my requirement above.

Answer 1

OK so if the SQL query does not have results then NULL is returned and, in essence, nothing is added to the $dbResults array. Instead lets append the results to a custom object. I don't know what PowerShell version you have so I needed to do something that I know should work. I also don't use the SQL cmdlets much so I had to guess for some of this.
$files = Get-ChildItem -Recurse -Force $filePath -ErrorAction SilentlyContinue |
Where-Object {$_.PSIsContainer -eq $false -and $_.Length -gt 1} |
Select-Object -ExpandProperty Name
$Server = "Loadv1"
$DB = "LoadDB"
$files | ForEach-Object{
write-host $_
$Query = "
SELECT FileName,CurrentStatus
FROM LogStatus
WHERE FileName LIKE '$_%'
"
$Results = Invoke-Sqlcmd -ServerInstance $Server -Database $DB -Query $Query
$props = #{Name = $_}
If($Results){
$props.CurrentStatus = $Results.CurrentStatus
} Else {
$props.CurrentStatus = "Null"
}
New-Object -TypeName PSCustomObject -Property $props
} | Format-Table -autosize
What this does is create a custom object that contains the results of the sql query (Which I did not change for reasons stated above). If there are no results returned we use the string "null" as a filler.
I cleaned up how you generated the $files variable by making is a simple string array with -Expand and moved the length condition there as well.
You should now have all the expected results. I say should since I am assuming what the return object looks like.

Answer 2

$Query = "
SELECT isNull(A.FileName, b.FileName) FileName,ISNULL(A.CurrentStatus,B.CurrentStatus) CurrentStatus
FROM LogStatus A
Right JOIN (SELECT '$filename' FileName,NULL CurrentStatus) B
ON a.Filename like '$filename%'
"
This should pad out the filenames for you. A little tough to prototype since it's in powershell but I might be able to come up with a sql fiddle to prove it.
EDIT
Answer edited, with sql fiddle:
http://sqlfiddle.com/#!3/12b43/9
Obviously, since you're in a cursor, we can only prove one query at a time.