Get-DbData.ps1
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.SYNOPSIS Execute a command against a SQL Server instance. .DESCRIPTION Executes a command with output sent to the Verbose stream. Commands can be non-queries, scalars, or return rows (the default), data tables, or a data set. For data tables and dataset, if the command is a simple Select statement against a single table (and optional simple Where clause), then Insert and Update/Delete statements (if a PK exists) are generated and an Alter() function added to the first data table. This can then be executed to trigger deletions (after modifying the rows in the table), or upserts (by passing in a hash table of column names and values). .PARAMETER SqlCommand. A SqlCommand likely from New-DbCommand. .PARAMETER TableMapping An optional list of custom table names to use for the result set, in order. By default these are Table, Table1, Table2, etc. .PARAMETER OutputAs The type of data to return. It can be scalar (the first column of the first row of a result set), a non query (an integer), datarows, datatables, or a dataset. .PARAMETER NoSchema For some simple operations, where no editing is required, you might want to skip schema gathering. .PARAMETER NoCommandBuild For some simple operations, where no editing is required, you might want to skip command building. .PARAMETER InfoMessageVariable An object of System.Collections.ArrayList which will be appended with all info message objects received while running the command, in addition to formatted versions written to the verbose stream. .INPUTS Pipe in an SqlCommand like from New-DbCommand. .OUTPUTS See the OutputAs parameter. .EXAMPLE $serverInstance = ".\SQL2016" New-DbConnection $serverInstance master | New-DbCommand "If Object_Id('dbo.Moo', 'U') Is Not Null Drop Table dbo.Moo; Create Table dbo.Moo (A Int Identity (1, 1) Primary Key, B Nvarchar(Max)); Dbcc Checkident('dbo.Moo', Reseed, 100);" | Get-DbData -OutputAs NonQuery | Out-Null $dbData = New-DbConnection $serverInstance master | New-DbCommand "Select * From dbo.Moo;" | Get-DbData -OutputAs DataTables $dbData.Alter(@{ B = "A" }) | Out-Null $dbData.Alter(@{ B = "B" }) | Out-Null $dbData.Alter(@{ A = 100; B = "C" }) | Out-Null $dbData.Alter(@{ A = 4; B = "D" }) | Out-Null $dbData Results: A B - - 100 C 101 B 102 D This drops and creates a dummy table with an identity column seeding at 100. It then inserts two rows, updates the first row, then attempts a fixed identity insert. The result is three rows, with the special identity of the last column discarded (but the properly allocated identity value returned). .EXAMPLE $serverInstance = ".\SQL2016" $infoMessage = New-Object System.Collections.ArrayList New-DbConnection $serverInstance master | New-DbCommand "Print 'Moo';" | Get-DbData -OutputAs NonQuery -InfoMessageVariable $infoMessage | Out-Null $infoMessage Results: Source : .Net SqlClient Data Provider Number : 0 State : 1 Class : 0 Server : .\SQL2016 Message : Moo Procedure : LineNumber : 1 Stores objects from the message stream into a variable (which is overwritten). #> function Get-DbData { [CmdletBinding()] param ( [Parameter(Mandatory = $true, ValueFromPipeline = $true)] [System.Data.SqlClient.SqlCommand] $SqlCommand, [string[]] $TableMapping = @(), [ValidateSet("NonQuery", "Scalar", "DataRows", "DataSet", "DataTables")] $OutputAs = "DataRows", [switch] $NoSchema, [switch] $NoCommandBuilder, $InfoMessageVariable = (New-Object Collections.ArrayList) ) begin { $infoMessageScript = { Set-StrictMode -Version Latest $ErrorActionPreference = "Stop" # Write-Error has been substituted for Write-Verbose here because otherwise it gets lost try { $_ | Select-Object -ExpandProperty Errors | ForEach-Object { [void] $InfoMessageVariable.Add($_) if ($_.Class -le 10) { "Msg {0}, Level {1}, State {2}, Line {3}$([Environment]::NewLine){4}" -f $_.Number, $_.Class, $_.State, $_.LineNumber, $_.Message | Write-Verbose } else { # Should be Write-Error but it doesn't seem to trigger properly (after -FireInfoMessageEventOnUserErrors) and so it would otherwise up getting lost "Msg {0}, Level {1}, State {2}, Line {3}$([Environment]::NewLine){4}" -f $_.Number, $_.Class, $_.State, $_.LineNumber, $_.Message | Write-Verbose } } } catch { "InfoMessage script error: $_" | Write-Verbose } }.GetNewClosure() # I know this isn't beautiful or awesome and I've forgotten how it works. # But it does work most of the time. $alterScript = { [CmdletBinding()] param ( $DataRows ) # Process multiple rows one at a time foreach ($row in $DataRows) { $table = $this # Get the incoming column names if ($row -is [System.Data.DataRow]) { $rowName = $row.Table.Columns | Select-Object -ExpandProperty ColumnName } elseif ($row -is [Hashtable]) { $rowName = $row.Keys } elseif ($row -is [PSObject]) { $newRow = @{} $row.psobject.Properties | ForEach-Object { $newRow.Add($_.Name, $_.Value) } $row = $newRow $rowName = $row.Keys } else { Write-Error "Unknown row type of $($row.GetType().FullName)" } # Get the primary key names and values, if any $pkName = $table.PrimaryKey | Select-Object -ExpandProperty ColumnName $pkValue = New-Object Collections.ArrayList foreach ($name in $pkName) { if ($rowName -contains $name) { [void] $pkValue.Add($row[$name]) } else { $pkValue = $null break } } if ($pkValue) { $newRow = $table.Rows.Find($pkValue.ToArray()) } else { $newRow = $null } if ($newRow) { foreach ($property in ($rowName | Where-Object { $pkName -notcontains $_ })) { if ($newRow[$property] -ne $row[$property]) { if ($null -ne $row[$property]) { $newRow[$property] = $row[$property] } else { $newRow[$property] = [DBNull]::Value } } } } else { $newRow = $table.NewRow() foreach ($property in $rowName) { if ($null -ne $row[$property]) { $newRow[$property] = $row[$property] } else { $newRow[$property] = [DBNull]::Value } } $table.Rows.Add($newRow) } } $sqlDataAdapter.Update($this) } } process { $SqlCommand.Connection.add_InfoMessage($infoMessageScript) try { $closeConnection = $false if ($SqlCommand.Connection.State -ne "Open") { $SqlCommand.Connection.Open() $closeConnection = $true } switch ($OutputAs) { "Scalar" { $scalar = $SqlCommand.ExecuteScalar() break } "NonQuery" { $nonQuery = $SqlCommand.ExecuteNonQuery() break } default { $sqlDataAdapter = New-Object System.Data.SqlClient.SqlDataAdapter($SqlCommand) $sqlDataAdapter.MissingSchemaAction = "AddWithKey" # Name the tables if they were passed in for ($i = 0; $i -lt $TableMapping.Count; $i++) { [void] $sqlDataAdapter.TableMappings.Add("Table$(if ($i -ne 0) { $i })", $TableMapping[$i]) } $dataSet = New-Object System.Data.DataSet if (!$NoSchema) { try { [void] $sqlDataAdapter.FillSchema($dataSet, [System.Data.SchemaType]::Mapped) } catch { Write-Verbose "Couldn't retrieve schema data $($sqlDataAdapter.SelectCommand.CommandText) because $_" } } [void] $sqlDataAdapter.Fill($dataSet) # Add Insert/Update/Delete commands if ($OutputAs -ne "DataRows" -and !$NoCommandBuilder -and $dataSet.Tables.Count -ne 0) { try { New-DisposableObject ($commandBuilder = New-Object System.Data.SqlClient.SqlCommandBuilder($sqlDataAdapter)) { # Insert commands are the most likely to generate because they don't need a PK $sqlDataAdapter.InsertCommand = $commandBuilder.GetInsertCommand().Clone() if ($identityColumn = $dataSet.Tables[0].Columns | Where-Object { $_.AutoIncrement -eq $true }) { $sqlDataAdapter.InsertCommand.CommandText += "; Select @Id = Scope_Identity();" $sqlDataAdapter.InsertCommand.Parameters.Add("@Id", [System.Data.SqlDbType]::BigInt, 0, $identityColumn.ColumnName).Direction = "Output" $sqlDataAdapter.InsertCommand.UpdatedRowSource = "OutputParameters" } # These will fail on tables without a PK $sqlDataAdapter.DeleteCommand = $commandBuilder.GetDeleteCommand().Clone() $sqlDataAdapter.UpdateCommand = $commandBuilder.GetUpdateCommand().Clone() } } catch { # Swallow. We can't write it verbosely because verbose is used for print statements. Write-Verbose "Couldn't build command for $($sqlDataAdapter.SelectCommand.CommandText) because $_" } if ($sqlDataAdapter.InsertCommand -or $sqlDataAdapter.UpdateCommand -or $sqlDataAdapter.DeleteCommand) { # Store a link to the data adapter against the first table along with the alter script Add-Member -InputObject $dataSet.Tables[0] -MemberType ScriptMethod -Name Alter -Value $alterScript.GetNewClosure() } } } } switch ($OutputAs) { "NonQuery" { $nonQuery break } "Scalar" { $scalar break } "DataRows" { $dataSet.Tables | Select-Object -ExpandProperty Rows break } "DataSet" { $dataSet break } default { $dataSet.Tables break } } } finally { if ($closeConnection -and $SqlCommand.Connection.State -eq "Open") { $SqlCommand.Connection.Close() } [void] $SqlCommand.Connection.remove_InfoMessage($infoMessageScript) } } end { } } |