1. A method realized by a computer for recognizing at least one table in one or more documents, comprising: parsing and analyzing metadata information in an original fixed-layout document, and extracting basic graphic elements on a page of the document; segmenting the basic graphic elements, extracting segmented text lines on the page which represent border lines of the table to be recognized within the page, and acquiring segments; constructing an undirected graph with respect to each of the segments; extracting an image on the page, detecting a plurality of intersection points formed by a plurality of horizontal lines and a plurality of vertical lines respectively, detecting an external envelop matrix formed by the plurality of intersection points, and taking whether the segmented text lines fall within the external envelop matrix as local relationship features which indicate whether the segmented text lines are parts of the table to be recognized; training a learning model according to the local relationship features, local features of the segments, and neighborhood relationship features among the segments, acquiring model parameters, and establishing a table recognizing model based on the acquired model parameters; and invoking the table recognizing model to perform table recognizing for the document, so as to get a recognizing result.