[mssql] Don't query ALL tables to retrieve single table details

Lightens load when browsing SQL Server connections via browser
qgis · Feb 23, 2025 · 19df56c · 19df56c
1 parent 8789841
commit 19df56c
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Showing 2 changed files with 31 additions and 6 deletions.
diff --git a/src/providers/mssql/qgsmssqlproviderconnection.cpp b/src/providers/mssql/qgsmssqlproviderconnection.cpp
@@ -330,23 +330,41 @@ long long QgssMssqlProviderResultIterator::rowCountPrivate() const
   return mQuery->size();
 }
 
+QgsAbstractDatabaseProviderConnection::TableProperty QgsMssqlProviderConnection::table( const QString &schema, const QString &table, QgsFeedback *feedback ) const
+{
+  const QList<QgsMssqlProviderConnection::TableProperty> properties { tablesPrivate( schema, table, TableFlags(), feedback ) };
+  if ( !properties.empty() )
+  {
+    return properties.first();
+  }
+  else
+  {
+    throw QgsProviderConnectionException( QObject::tr( "Table '%1' was not found in schema '%2'" )
+                                            .arg( table, schema ) );
+  }
+}
 
 QList<QgsMssqlProviderConnection::TableProperty> QgsMssqlProviderConnection::tables( const QString &schema, const TableFlags &flags, QgsFeedback *feedback ) const
+{
+  return tablesPrivate( schema, QString(), flags, feedback );
+}
+
+QList<QgsAbstractDatabaseProviderConnection::TableProperty> QgsMssqlProviderConnection::tablesPrivate( const QString &schema, const QString &table, const TableFlags &flags, QgsFeedback *feedback ) const
 {
   checkCapability( Capability::Tables );
   QList<QgsMssqlProviderConnection::TableProperty> tables;
 
   const QgsDataSourceUri dsUri { uri() };
 
   // Defaults to false
-  const bool useGeometryColumnsOnly { dsUri.hasParam( QStringLiteral( "geometryColumnsOnly" ) ) && ( dsUri.param( QStringLiteral( "geometryColumnsOnly" ) ) == QLatin1String( "true" ) || dsUri.param( QStringLiteral( "geometryColumnsOnly" ) ) == '1' ) };
+  const bool useGeometryColumnsOnly { !table.isEmpty() && ( dsUri.hasParam( QStringLiteral( "geometryColumnsOnly" ) ) && ( dsUri.param( QStringLiteral( "geometryColumnsOnly" ) ) == QLatin1String( "true" ) || dsUri.param( QStringLiteral( "geometryColumnsOnly" ) ) == '1' ) ) };
 
   // Defaults to true
   const bool useEstimatedMetadata { !dsUri.hasParam( QStringLiteral( "estimatedMetadata" ) ) || ( dsUri.param( QStringLiteral( "estimatedMetadata" ) ) == QLatin1String( "true" ) || dsUri.param( QStringLiteral( "estimatedMetadata" ) ) == '1' ) };
 
   // Defaults to true because we want to list all tables if flags are not set
   bool allowGeometrylessTables;
-  if ( flags == 0 )
+  if ( flags == 0 || !table.isEmpty() )
   {
     allowGeometrylessTables = true;
   }
@@ -355,6 +373,11 @@ QList<QgsMssqlProviderConnection::TableProperty> QgsMssqlProviderConnection::tab
     allowGeometrylessTables = flags.testFlag( TableFlag::Aspatial );
   }
   const bool disableInvalidGeometryHandling = dsUri.hasParam( QStringLiteral( "disableInvalidGeometryHandling" ) ) && dsUri.param( QStringLiteral( "disableInvalidGeometryHandling" ) ).toInt();
+  QString tableNameFilter;
+  if ( !table.isEmpty() )
+  {
+    tableNameFilter = QStringLiteral( " AND sys.objects.name = %1" ).arg( QgsMssqlProvider::quotedValue( table ) );
+  }
 
   QString query { QStringLiteral( "SELECT " ) };
 
@@ -375,11 +398,11 @@ QList<QgsMssqlProviderConnection::TableProperty> QgsMssqlProviderConnection::tab
                                 JOIN sys.schemas
                                   ON sys.objects.schema_id = sys.schemas.schema_id
                                 WHERE
-                                  sys.schemas.name = %1
+                                  sys.schemas.name = %1 %2
                                   AND (sys.types.name = 'geometry' OR sys.types.name = 'geography')
                                   AND (sys.objects.type = 'U' OR sys.objects.type = 'V')
                              )raw" )
-               .arg( QgsMssqlProvider::quotedValue( schema ) );
+               .arg( QgsMssqlProvider::quotedValue( schema ), tableNameFilter );
   }
 
   if ( allowGeometrylessTables )
@@ -391,15 +414,15 @@ QList<QgsMssqlProviderConnection::TableProperty> QgsMssqlProviderConnection::tab
                                JOIN sys.schemas
                                   ON sys.objects.schema_id = sys.schemas.schema_id
                              WHERE
-                               sys.schemas.name = %1
+                               sys.schemas.name = %1 %2
                                AND NOT EXISTS
                                 (SELECT *
                                   FROM sys.columns sc1 JOIN sys.types ON sc1.system_type_id = sys.types.system_type_id
                                   WHERE (sys.types.name = 'geometry' OR sys.types.name = 'geography')
                                     AND sys.objects.object_id = sc1.object_id )
                                AND (sys.objects.type = 'U' OR sys.objects.type = 'V')
                              )raw" )
-               .arg( QgsMssqlProvider::quotedValue( schema ) );
+               .arg( QgsMssqlProvider::quotedValue( schema ), tableNameFilter );
   }
 
   const QList<QVariantList> results { executeSqlPrivate( query, false ).rows() };

diff --git a/src/providers/mssql/qgsmssqlproviderconnection.h b/src/providers/mssql/qgsmssqlproviderconnection.h
@@ -60,6 +60,7 @@ class QgsMssqlProviderConnection : public QgsAbstractDatabaseProviderConnection
     void dropSchema( const QString &name, bool force = false ) const override;
     QgsAbstractDatabaseProviderConnection::QueryResult execSql( const QString &sql, QgsFeedback *feedback ) const override;
     QList<QgsAbstractDatabaseProviderConnection::TableProperty> tables( const QString &schema, const TableFlags &flags = TableFlags(), QgsFeedback *feedback = nullptr ) const override;
+    QgsAbstractDatabaseProviderConnection::TableProperty table( const QString &schema, const QString &table, QgsFeedback *feedback = nullptr ) const override;
     QStringList schemas() const override;
     void store( const QString &name ) const override;
     void remove( const QString &name ) const override;
@@ -72,6 +73,7 @@ class QgsMssqlProviderConnection : public QgsAbstractDatabaseProviderConnection
     void setDefaultCapabilities();
     void dropTablePrivate( const QString &schema, const QString &name ) const;
     void renameTablePrivate( const QString &schema, const QString &name, const QString &newName ) const;
+    QList<QgsAbstractDatabaseProviderConnection::TableProperty> tablesPrivate( const QString &schema, const QString &table, const TableFlags &flags = TableFlags(), QgsFeedback *feedback = nullptr ) const;
 
     static const QStringList EXTRA_CONNECTION_PARAMETERS;
 };