Figure 1.1 A simplified database system environment.prabakar/database/cmaps/... · Figure 2.3...
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Transcript of Figure 1.1 A simplified database system environment.prabakar/database/cmaps/... · Figure 2.3...
Figure 1.1 A simplified database system environment.
Users/Programmers---------~------DatabaseSystem
Application Programs/Oueries
DBMSSoftware Software to Process
Oueries/ Programs
Software to Access&oredD~a
Stored DatabaseDefinition(Meta-Data)- -
Stored Database
Figure 2.2 The three-schema architecture.
® External Level ExternalView
External/ConceptualMapping
CD cconceptual Le~
\ Conceptual/Internal11 Mapping
~aILev~
End Users
~O' ~External ~View '2
L-------ll.~
____C_o_n_c_e~p_tu~a_I_S_c_he_m__a 1 (I)
Internal Schema
EJStored Database
ALWAYS LEARNING ' " '. ."' . ~ , . ", .' PEARSON. .
, ~ ~ ~
Figure 2.3 Component modules of a DBMS and their interactions.
Users:
DOLCompiler
, /
//
//
/
/
Query and TransactionExecution:
PrivilegedCommands
Casual Users
QueryCompiler
i
QueryOptimizer
/
/
/
/
DBA Commands,Queries, and Transactions/
/
Parametric Users
DMLCompiler
CompiledTransactions
Runtime~I Database
Processor
,-------,Stored Database
, , •.(.)4" i
~
/
//
//
StoredData
ManagerConcurrency ControllBackuplRecoverySubsystems
Input/Outputfrom Database
ALWAYS LEARNING PEARSON
