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

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Part of PowerShell module : GenXdev.Data.SqlServer
Original cmdlet filename : Get-SQLServerViewSchema.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 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.
 
.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.Data\Invoke-SQLServerQuery @PSBoundParameters
    }

    end {
    }
}