1. A computer program product comprising a computer readable storage medium having a computer readable program stored therein, wherein the computer readable program, when executed on a processor of a computing device, causes the computing device to implement a stream computing platform, wherein the computer readable program causes the computing device to: build, by a machine learning component executing within the stream computing platform, a model for each input data stream in the stream computing platform, wherein each tuple of each given input data stream is tagged with a key corresponding to the given input data stream; perform, by an operator component executing within the stream computing platform, an operation on each input data stream using its corresponding model; detect, by a change detection component executing within the stream computing platform, a misdirected input data stream, wherein the misdirected input data stream is tagged with a key that does not correspond to the misdirected input data stream; pause, by the change detection component, the misdirected input data stream; and swap, by a model swapping component executing within the stream computing platform, a model corresponding to the misdirected input data stream with another model corresponding to another paused input data stream.