Belin.Sql

1.0.1

src/Cmdlets/Invoke-Query.psm1

using namespace System.Data
using module ../SqlCommand.psm1
using module ../SqlMapper.psm1
using module ../SqlParameterCollection.psm1

<#
.SYNOPSIS
    Executes a parameterized SQL query and returns a sequence of objects whose properties correspond to the columns.
.OUTPUTS
    The sequence of object tuples whose properties correspond to the columns.
#>
function Invoke-Query {
    [CmdletBinding()]
    [OutputType([object])]
    param (
        # The connection to the data source.
        [Parameter(Mandatory, Position = 0)]
        [IDbConnection] $Connection,

        # The command to be executed.
        [Parameter(Mandatory, Position = 1)]
        [SqlCommand] $Command,

        # The parameters of the SQL statement.
        [Parameter(Position = 2)]
        [SqlParameterCollection] $Parameters,

        # The type of objects to return.
        [ValidateCount(1, 7)]
        [Type[]] $As = @([psobject]),

        # The fields from which to split and read the next objects.
        [ValidateCount(0, 6)]
        [string[]] $SplitOn = @()
    )

    begin {
        $dbCommand = $null
        $reader = $null
        if ($Connection.State -eq [ConnectionState]::Closed) { $Connection.Open() }
    }

    end {
        $dbCommand = $Command.ToDbCommand($Connection, $Parameters)
        $reader = $dbCommand.ExecuteReader()
        while ($reader.Read()) {
            $As.Count -gt 1 ? [SqlMapper]::Instance.CreateInstance($As, $reader, $SplitOn) : [SqlMapper]::Instance.CreateInstance($As[0], $reader)
        }
    }

    clean {
        ${reader}?.Close()
        ${dbCommand}?.Dispose()
    }
}