Powershell - SQL query result to variable with properties

问题

Why the stored output of SQLCMD has only Length property instead of column names?. Is it not possible to store sqlcmd output with its properties?

Invoke-sqlcmd stores it correctly but Invoke-SQLcmd takes a bit longer to process so I'm trying to make it work with SQLcmd as this method will be part of different scripts that are scheduled to run every minute, once ever hour etc.,

Any idea if this is possible or what the issue is?

Store output and echo $var:

     PS C:> $var=(SQLCMD -S 'x.x.x.x' -U 'user' -P 'password' -i "C:\query.sql" -W -m 1) 

     PS C:> $var
     job_id name
     ------ ----
     12345-aaaa-1234-5678-000000000000000 Clear DB entries
     12345-bbbb-1234-5678-000000000000000 TempLog DB

Echo $var[0,1,2] which doesn't show property names.

     PS C:> $var[0]
     job_id name
     PS C:> $var[1]
     ------ ----
     PS C:> $var[2]
     12345-aaaa-1234-5678-000000000000000 Clear DB entries

Show $var properties

     PS C:> $var | select *
     Length
     ------
     11
     53

Show $var type

     PS C:> $var.GetType()

     IsPublic IsSerial Name                                     BaseType
     -------- -------- ----                                     --------
     True     True     Object[]                                 System.Array

回答1:

$var=(SQLCMD -S 'x.x.x.x' -U 'user' -P 'password' -i "C:\query.sql" -W -m 1)

You're calling sqlcmd.exe, which has no concept of what .Net objects are let alone how to pass them to PowerShell. As far as PowerShell is concerned, that command outputs strings. You will need to convert the strings to objects yourself.

If you have to use sqlcmd.exe, I would suggest something like this:

$Delimiter = "`t"
$var = SQLCMD -S 'x.x.x.x' -U 'user' -P 'password' -i "C:\query.sql" -W -m 1 -s $Delimiter |
    ConvertFrom-Csv -Delimiter $Delimiter |
    Select-Object -Skip 1

I'm using tab as the field separator. If your data contains tabs, you'll need a different separator. You could also run into problems if your data contains double quotes. The Select-Object -Skip 1 is to skip the underline row that sqlcmd always creates below the header.

Also be aware that you should use the -w parameter on sqlcmd to prevent any incorrect wrapping. Also beware that null values are always output as a literal string NULL.

That said, I would still probably stick with Invoke-Sqlcmd. It's much less error prone and much more predictable. If I really needed performance, I'd probably use direct .Net methods or SSIS.

回答2:

I have written a function for that purpose... ist not fully fleshed out... hope it helps

    function Invoke-MSSqlCommand
    {
      [CmdletBinding()]
      param
      (
        [Parameter(Position=0, Mandatory=$true)]
        [ValidateNotNullOrEmpty()]
        [string]
        $Query,

        [Parameter(Position=1, Mandatory=$true)]
        [ValidateNotNullOrEmpty()]
        [string]
        $ConnectionString,

        [Switch]
        $NoOutput
      )
      try {
        $connection = New-Object -TypeName System.Data.SqlClient.SqlConnection
        $connection.ConnectionString = $ConnectionString
        $null = $connection.Open()
      }
      catch {
        Throw "$connectionstring could not be contacted"
      }
      $command = New-Object -TypeName System.Data.SqlClient.SqlCommand
      $command.CommandText = $query
      $command.Connection = $connection


      if ($NoOutput) {
        $null = $command.ExecuteNonQuery()
      }
      else {

        if ($dataset.Tables[0].Rows[0] -eq $null) {
          write-verbose -Message 'no record'
          $connection.Close()
          return $null
        }

        $dataset.Tables[0].Rows
        $connection.close()
      }
    }

来源：https://stackoverflow.com/questions/49284778/powershell-sql-query-result-to-variable-with-properties

标签

powershell

sqlcmd

invoke-sqlcmd