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

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<#
.SYNOPSIS
Retrieves the SQL schema definition for a SQL Server view.

.DESCRIPTION
This function queries the SQL Server database's system tables to extract the SQL
definition of a specified view. It supports connecting via either a connection
string or database name with server parameters and returns the complete SQL schema
that defines the requested view.

.LICENSE
Copyright (C) 2026 René Vaessen / GenXdev

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program. If not, see <https://www.gnu.org/licenses/>.

.PARAMETER ConnectionString
The connection string used to connect to the SQL Server database. This parameter is
mutually exclusive with DatabaseName.

.PARAMETER DatabaseName
The name of the SQL Server database. This parameter is mutually exclusive with
ConnectionString.

.PARAMETER Server
The SQL Server instance name. Defaults to 'localhost'.

.PARAMETER ViewName
The name of the view whose schema definition should be retrieved.

.EXAMPLE
Get-SQLServerViewSchema -DatabaseFilePath "C:\Databases\MyApp.sqlite" `
                    -ViewName "CustomerOrders"

#>

function Get-SQLServerViewSchema {

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

    begin {

        # log the start of view schema retrieval
        Microsoft.PowerShell.Utility\Write-Verbose "Retrieving schema for view: $ViewName"
    }


    process {

        # construct query to fetch the view definition from SQL Server system views
        $query = "SELECT OBJECT_DEFINITION(OBJECT_ID('$ViewName')) AS view_definition"

        # log the query being executed
        Microsoft.PowerShell.Utility\Write-Verbose "Executing query: $query"

        # add the query to parameters and execute it using Invoke-SQLServerQuery
        $PSBoundParameters['Queries'] = $query
        GenXdev\Invoke-SQLServerQuery @PSBoundParameters
    }

    end {
    }
}