a time series object, a two column data frame or object of S3 class
miro (meta information for R objects).
...
optional arguments, fct = TRUE create text expressions of hstore function calls.
also for data.frames key_pos and value_pos could be given if they are different from 1 and 2.
e.g. position of the key col and
pasition of the value col in a data.frame.
Details
This function creates a key value pair mapping from a time series object.
It returns an hstore object that can be inserted to a PostgreSQL database relation field of type hstore.