This component consists of three modules: the 

Resource Manager, Memory 

Manager,

 and the 

Storage Manager

. When the Resource Manager receives and 

accepts a request from the Execution Engine, this request is forwarded to the 

Memory Manager. The Memory Manager allocates memory resources to meet 

the demand for the request, and returns the references of the requested data 

within memory to the Resource Manager, which then forwards the data to the 

Execution Engine. The role of the Storage Manager is to mediate between the 

Memory Manager and the secondary storage. 

Physical resource

This layer is the bottom layer of the RDBMS architecture, and represents the 

main and virtual memory, and the secondary storage or physical disk. This layer 

is accessed through the storage management to store or retrieve data. Data 

stored in a RDBMS is usually:

Data files (user data)

Data dictionary (metadata)

Indices

Log information

Statistical data

1.2.2  MySQL design and SQL compliance

In this section, the following topics are discussed:

MySQL directory structure

MySQL table types

MySQL standard SQL compliance

MySQL directory structure

MySQL can be installed as one or more database within one server. For each 

database, MySQL creates a directory that holds data and indexes. Figure 1 13 

shows the directory structure for a binary installation on SuSE Linux. Red Hat 

has similar directory structure.

32 

MySQL to DB2 UDB Conversion Guide