All the 3 engines are physically stored on both the client machine & Intelligence Server(IS) machine. The use of this component is dictated by the configurations of the system ( 2 tier / 3 tier / higher ).
2 Tier Configuration System:
In this system, the client connects directly to the DWH & MD databases and the MicroStrategy engine components are invoked on the clients side. The SQL Engine can be loaded on demand on either the client side ( in 2 tier ) or on Intelligence Server ( in 3 tier ).
For eg: if we run a report in MicroStrategy Desktop ( 2- tier ) , the SQL Engine component in MicroStrategy Desktop is invoked to perform the SQL generation. Similarly, in a 2 tier configuration, the Analytical engine component on MicroStrategy(MSTR) Desktop is invoked to perform the formatting.
3 Tier / 4 Tier Configuration System:
In this systems, the client establishes the connectivity to the DWH & MD Databases through Intelligence Server, so the MicroStrategy engine components are invoked on the IS Side.
For eg: if we are running a report in MSTR web in a 4 tier environment, the SQL engine component on IServer is invoked to perform the SQL generation and the Analytical engine component on IServer is invoked to format the required results.
Hope the above one clearly explains about the Placement of MicroStrategy Engine Components on differenct configuration systems.
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