Database System Concepts
This popular text in database systems is used in departments of computer science, computer engineering, and electrical engineering. The revision includes more material on SQL, relational models, logical databases, "QB" and "Datalog."
Results 1-3 of 83
Once a log record exists we can output the modification to the database if this is
desirable. Also, we have the ability to undo a modification that has already been
output to the database. This is accomplished by using the old-value field in log
records. In order for log records to be useful for recovery from system and disk
failures, the log must reside in stable storage. For now, we assume that , every
log record is written to stable storage as soon as it is created. In Section 10.5 we
shall see ...
Output all log records currently residing in main memory onto stable storage. 2.
Output all modified buffer blocks to the disk. 3. Output a log record <checkpoint>
onto stable storage. The presence of a <checkpoint> record in the log allows the
system to streamline its recovery procedure. Consider a transaction T, that
committed prior to the checkpoint. For such a transaction, the <Tj commits>
record appears in the log before the <checkpoint> record. Any database
modifications made by ...
13.9 Scheme Modification In the introduction to this chapter, we noted that the
types of modification that can be made to a relational database scheme are fairly
simple: • Create or drop a relation. • Add or delete attributes from a relation
scheme. This simplicity does not hold for object-oriented database schemes. The
complication arises from two sources: • Complex changes. The types of
modification that can be made to an object-oriented scheme are more complex
than those that can ...
What people are saying - Write a review
LibraryThing ReviewUser Review - IvanIdris - LibraryThing
This book teaches about the inner workings, the nuts and bolts of databases without requiring a lot of prior knowledge: Data Models Relational Databases Object Based Databases and XML Data Storage and ... Read full review
Relational Commercial Languages
38 other sections not shown