Get-DbaDbTable: Fix performance regression with URN filter and config option (#10140)

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

Author: PeterSawatzki-MGGM

.gitignore

@@ -60,3 +60,7 @@ allcommands.ps1
 /.shadowgit.git
 /.claude
 publish.ps1
+
+PR_BODY.md
+
+PR_DESCRIPTION.md

private/configurations/settings/commands.ps1

@@ -16,3 +16,6 @@ Set-DbatoolsConfig -FullName 'commands.initialize-credssp.bypass' -Value $false
 
 # Test-ElevationRequirement
 Set-DbatoolsConfig -FullName 'commands.test-elevationrequirement.disable' -Value $false -Initialize -Validation bool -Description "Disable elevation (run as admin) requirement"
+
+# Get-DbaDbTable
+Set-DbatoolsConfig -FullName 'commands.get-dbadbtable.clearandinitialize' -Value $false -Initialize -Validation bool -Description "Controls whether Get-DbaDbTable uses ClearAndInitialize to load all table properties in one optimized query. Set to true to enable the optimization, which loads all properties in a single query but clears already loaded SMO properties. Keep at false when reusing SMO objects across multiple calls (e.g. in Copy-DbaDbTableData)."

public/Get-DbaDbTable.ps1

@@ -209,7 +209,77 @@ function Get-DbaDbTable {
                 $null = $properties.Add('IsEdge')
             }
 
-            $db.Tables.ClearAndInitialize('', [string[]]$properties)
+            # Build URN filter for server-side filtering when -Table or -Schema is specified
+            # This avoids loading ALL tables when only specific ones are requested
+            $urnFilter = ''
+            if ($fqTns -or $Schema) {
+                $filterConditions = [System.Collections.ArrayList]@()
+
+                # Add schema filter conditions from -Schema parameter
+                if ($Schema) {
+                    $schemaConditions = [System.Collections.ArrayList]@()
+                    foreach ($s in $Schema) {
+                        $null = $schemaConditions.Add("@Schema='$s'")
+                    }
+                    if ($schemaConditions.Count -eq 1) {
+                        $null = $filterConditions.Add($schemaConditions[0])
+                    } elseif ($schemaConditions.Count -gt 1) {
+                        $null = $filterConditions.Add("($($schemaConditions -join ' or '))")
+                    }
+                }
+
+                # Add table name filter conditions from -Table parameter
+                if ($fqTns) {
+                    $tableConditions = [System.Collections.ArrayList]@()
+                    foreach ($fqTn in $fqTns) {
+                        # Skip if database is specified and doesn't match current database
+                        if ($fqTn.Database -and $fqTn.Database -ne $db.Name) {
+                            continue
+                        }
+
+                        # Only add the table name filter, schema is handled above via -Schema parameter
+                        # or from the parsed table name if -Schema was not specified
+                        $tableParts = [System.Collections.ArrayList]@()
+
+                        # Add schema from table name only if -Schema parameter was not specified
+                        if ($fqTn.Schema -and -not $Schema) {
+                            $null = $tableParts.Add("@Schema='$($fqTn.Schema)'")
+                        }
+
+                        if ($fqTn.Table) {
+                            $null = $tableParts.Add("@Name='$($fqTn.Table)'")
+                        }
+
+                        if ($tableParts.Count -gt 0) {
+                            if ($tableParts.Count -eq 1) {
+                                $null = $tableConditions.Add($tableParts[0])
+                            } else {
+                                $null = $tableConditions.Add("($($tableParts -join ' and '))")
+                            }
+                        }
+                    }
+
+                    if ($tableConditions.Count -gt 0) {
+                        if ($tableConditions.Count -eq 1) {
+                            $null = $filterConditions.Add($tableConditions[0])
+                        } else {
+                            $null = $filterConditions.Add("($($tableConditions -join ' or '))")
+                        }
+                    }
+                }
+
+                if ($filterConditions.Count -gt 0) {
+                    # ClearAndInitialize expects XPath-style filter WITH outer brackets
+                    # e.g., "[@Schema='dispo' and @Name='t_auftraege']"
+                    # See: https://learn.microsoft.com/en-us/dotnet/api/microsoft.sqlserver.management.smo.smocollectionbase.clearandinitialize
+                    $urnFilter = "[$($filterConditions -join ' and ')]"
+                    Write-Message -Level Verbose -Message "Using URN filter: $urnFilter"
+                }
+            }
+
+            if (Get-DbatoolsConfigValue -FullName 'commands.get-dbadbtable.clearandinitialize') {
+                $db.Tables.ClearAndInitialize($urnFilter, [string[]]$properties)
+            }
 
             if ($fqTns) {
                 $tables = @()