1. A method performed by a consistency checker for finding inconsistencies of data posts stored in a data repository, the consistency checker having access to a number of inconsistency patterns, each inconsistency pattern being associated with an inconsistency analysis rule for a value of a data attribute, the method comprising: receiving a data post from the data repository; matching a value of a data attribute of the data post with a value of a corresponding data attribute of the stored inconsistency patterns; if there is a match, applying the inconsistency analysis rule that is connected with the matched inconsistency pattern to the data post to evaluate whether there is an inconsistency in the data post or not, wherein the number of inconsistency patterns each defines an inconsistency that has previously occurred for the value of the data attribute in the data repository, wherein each of the number of inconsistency patterns has a probability weight, the probability weight indicating a frequency of inconsistency of each of the inconsistency patterns that occurred for the data posts in the data repository; and if there is more than one match, selecting inconsistency pattern in an inconsistency pattern order according to the probability weight for each matched inconsistency pattern.