![[Contents]](FIGURE/CONTENT.GIF)
OpenTP1 Version 7 Programming Guide
![[Index]](FIGURE/INDEX.GIF)
![[Back]](FIGURE/FRONT.GIF)
![[Next]](FIGURE/AFTER.GIF)
A TAM file comprises data items. Each data item is called a record. The TAM file keys and records are loaded into the memory. Fast access to a file from a UAP is enabled by accessing the key in the memory instead of accessing the actual file. The index part and data part are called a TAM table.
A TAM table consists of the following two parts:
Index types are categorized into a hash format and a tree format. A method of corresponding keys to records is different between the hash format and the tree format. When accessing a TAM table, verify the index type of the TAM table, then create a UAP. If access is made to a TAM table of a different index type, the UAP TAM access function returns with an error.
TAM tables can be accessed only in online environment. TAM tables cannot be accessed in offline environment. To access a TAM table from a UAP, use the access mode specified in the TAM service definition. If another access mode is used, the UAP TAM access function returns with an error.
The figure below shows the TAM file configuration.
Figure 4-6 TAM file configuration
![[Figure]](FIGURE/ZU040600.GIF)
All Rights Reserved. Copyright (C) 2006, 2010, Hitachi, Ltd.