Example #1
0
        /// <summary>
        /// Checks whether the target column is an identity field from the database.
        /// </summary>
        /// <typeparam name="TEntity"></typeparam>
        /// <param name="connectionString">The connection string object to be used.</param>
        /// <param name="command">The target command.</param>
        /// <param name="columnName">The name of the column.</param>
        /// <returns>A boolean value indicating the identification of the column.</returns>
        public static bool IsIdentity <TEntity>(string connectionString, Command command, string columnName)
            where TEntity : class
        {
            var isIdentity = false;

            // Open a connection
            using (var connection = new SqlConnection(connectionString).EnsureOpen())
            {
                var commandType = CommandTypeCache.Get <TEntity>(command);

                // Check for the command type
                if (commandType != CommandType.StoredProcedure)
                {
                    var mappedName  = ClassMappedNameCache.Get <TEntity>(command);
                    var commandText = @"
                        SELECT CONVERT(INT, c.is_identity) AS IsIdentity
                        FROM [sys].[columns] c
                        INNER JOIN [sys].[objects] o ON o.object_id = c.object_id
                        WHERE (c.[name] = @ColumnName)
	                        AND (o.[name] = @TableName)
	                        AND (o.[type] = 'U');"    ;

                    // Open a command
                    using (var dbCommand = connection.EnsureOpen().CreateCommand(commandText))
                    {
                        // Create parameters
                        dbCommand.CreateParameters(new
                        {
                            ColumnName = columnName.AsUnquoted(),
                            TableName  = mappedName.AsUnquoted()
                        });

                        // Execute and set the result
                        var result = dbCommand.ExecuteScalar();
                        if (result != null && result != DBNull.Value)
                        {
                            isIdentity = Convert.ToBoolean(result);
                        }
                    }
                }
            }

            // Return the value
            return(isIdentity);
        }
Example #2
0
        /// <summary>
        /// Gets the cached field definitions of the entity.
        /// </summary>
        /// <typeparam name="TEntity">The type of the target entity.</typeparam>
        /// <param name="command">The target command</param>
        /// <param name="connectionString">The connection string to be used.</param>
        /// <returns>The cached field definitions of the entity.</returns>
        public static IEnumerable <FieldDefinition> Get <TEntity>(Command command, string connectionString)
            where TEntity : class
        {
            var key    = $"{typeof(TEntity).FullName}.{command.ToString()}";
            var result = (IEnumerable <FieldDefinition>)null;

            if (m_cache.TryGetValue(key, out result) == false)
            {
                var commandType = CommandTypeCache.Get <TEntity>(command);
                if (commandType != CommandType.StoredProcedure)
                {
                    var tableName = ClassMappedNameCache.Get <TEntity>(command);
                    result = SqlDbHelper.GetFieldDefinitions(connectionString, tableName);
                }
                m_cache.TryAdd(key, result);
            }
            return(result);
        }