13. A method for determining recommendation data, comprising: extracting a first set of keywords from a set of user action logs that occurred prior to a predetermined time point; extracting a second set of keywords from a set of user action logs that occurred subsequent to the predetermined time point; merging at least a portion of the first set of keywords and at least a portion of the second set of keywords to obtain a third set of keywords; matching, using one or more processors, at least one keyword in the third set of keywords with a database of data that can potentially be recommended to a user; and in the event that a piece of data in the database is determined to match the at least one keyword from the third set of keywords, determining that the piece of data is to be recommended to the user.
13. A method for determining recommendation data, comprising: extracting a first set of keywords from a set of user action logs that occurred prior to a predetermined time point; extracting a second set of keywords from a set of user action logs that occurred subsequent to the predetermined time point; merging at least a portion of the first set of keywords and at least a portion of the second set of keywords to obtain a third set of keywords; matching, using one or more processors, at least one keyword in the third set of keywords with a database of data that can potentially be recommended to a user; and in the event that a piece of data in the database is determined to match the at least one keyword from the third set of keywords, determining that the piece of data is to be recommended to the user. 21. The method of claim 13 , wherein matching the at least one keyword in the third set of keywords to the piece of data to potentially recommend includes determining whether a keyword associated with the piece of data matches any keyword from the third set of keywords.