Functions/GenXdev.Data.SqlServer/Get-SQLServerViewData.ps1

<##############################################################################
Part of PowerShell module : GenXdev.Data.SqlServer
Original cmdlet filename : Get-SQLServerViewData.ps1
Original author : René Vaessen / GenXdev
Version : 1.300.2025
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Copyright (c) René Vaessen / GenXdev
 
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
 
    http://www.apache.org/licenses/LICENSE-2.0
 
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
################################################################################>

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<#
.SYNOPSIS
Retrieves data from a SQL database view with optional record limiting.
 
.DESCRIPTION
Queries a SQL database view using either a connection string or database file
path. The function supports limiting the number of returned records and provides
verbose output for tracking query execution.
 
.PARAMETER ConnectionString
The connection string to connect to the SQL database. This parameter is
mutually exclusive with DatabaseFilePath.
 
.PARAMETER DatabaseFilePath
The file path to the SQL database file. This parameter is mutually exclusive
with ConnectionString.
 
.PARAMETER ViewName
The name of the view from which to retrieve data.
 
.PARAMETER Count
The maximum number of records to return. Use -1 to return all records.
Defaults to 100 if not specified.
 
.EXAMPLE
Get-SQLServerViewData -DatabaseFilePath "C:\MyDb.sqlite" `
    -ViewName "CustomerView" `
    -Count 50
 
.EXAMPLE
Get-SQLServerViewData "C:\MyDb.sqlite" "CustomerView"
#>

function Get-SQLServerViewData {

    [CmdletBinding(DefaultParameterSetName = 'DatabaseName')]
    param (
        ########################################################################
        [Parameter(
            Position = 0,
            Mandatory = $true,
            ParameterSetName = 'ConnectionString',
            HelpMessage = 'The connection string to the SQL Server database.'
        )]
        [ValidateNotNullOrEmpty()]
        [string]$ConnectionString,

        ########################################################################
        [Parameter(
            Position = 0,
            Mandatory = $true,
            ParameterSetName = 'DatabaseName',
            HelpMessage = 'The name of the SQL Server database.'
        )]
        [ValidateNotNullOrEmpty()]
        [string]$DatabaseName,

        ########################################################################
        [Parameter(
            Position = 1,
            ParameterSetName = 'DatabaseName',
            HelpMessage = 'The SQL Server instance name.'
        )]
        [string]$Server = 'localhost',

        ########################################################################
        [Parameter(
            Position = 2,
            Mandatory = $true,
            HelpMessage = 'The name of the view to query.'
        )]
        [ValidateNotNullOrEmpty()]
        [string]$ViewName,

        ########################################################################
        [Parameter(
            Position = 3,
            Mandatory = $false,
            HelpMessage = 'Number of records to return. -1 for all records.'
        )]
        [ValidateRange(-1, [int]::MaxValue)]
        [int]$Count = 100
    )

    begin {

        Microsoft.PowerShell.Utility\Write-Verbose "Starting Get-SQLServerViewData for view: $ViewName"
    }


    process {

        # construct query with optional record limit
        $query = if ($Count -eq -1) {
            "SELECT * FROM $ViewName"
        }
        else {
            "SELECT * FROM $ViewName LIMIT $Count"
        }

        Microsoft.PowerShell.Utility\Write-Verbose "Executing query: $query"

        # prepare parameters for Invoke-SQLServerQuery
        $PSBoundParameters['Queries'] = $query

        # execute query and return results
        GenXdev.Data\Invoke-SQLServerQuery @PSBoundParameters
    }

    end {

        Microsoft.PowerShell.Utility\Write-Verbose "Completed querying view: $ViewName"
    }
}