Gio Wiederhold, File Organization for DataBase Design, McGraw Hill, 1987.  Home/Search   Document Not in Database   Summary   Related Articles   Check

....so that no more than two characters need to be looked at to know what type of data is being transmitted. The basic form of the exchange format is given in Figure 1. Punctuation indentation marks such as colon, 1 Self describing data exchange formats exist in several forms in earlier work [18, 22, 15]. 2 Data Type Data Layout Remarks Unit ( Booleans true false Numbers 123 Positive numbers 123.123 123 Negative numbers 123.123 Strings a string String is put inside double quotes Records (#l 1 : O 1 , Record is put inside round brackets. The label value triplets ....

G. Wiederhold. File Organization for Database Design. McGraw-Hill Book Company, New York, 1987.

....conceptual design an important part of the knowledge which is used for tuning schemes is already available [CoG93, Sha92, Su85] The internal database representation is based on well known data structuring techniques. The complexity of corresponding operational support is well known [KoS91, Wie87] There exists a general mechanism [SST94, ScT94] which allows the computation of integrity maintening procedures for the database implementation. Therefore, RADD enhances the conceptual database design phase by considering operational behaviour too. Elimination of operational bottlenecks and ....

G. Wiederhold, File Organization for Database Design. McGraw-Hill, 1987.

....representation frames [G 92, Mos83, MY89] and many others. 1.1 The OEM Model Most applications that have to deal with unpredictable, unstructured information use a selfdescribing model, where each data item has an associated descriptive label. Applications include tagged file systems [Wie87] Lotus Notes [Mar93] the Teknekron Information Bus [O 93] LOOM frames [MY89] electronic mail, RFC1532 bibliographic records, and many more. In [PGMW] we have defined a self describing data model, called the Object Exchange Model (OEM) which captures the essential features of the models ....

G. Wiederhold. File Organization for Database Design. McGraw Hill, New York, 1987.

....R 1 and R 2 . If we only represent parent to first child link and last child to parent link, then we can use foreign key links based on the values of X 1 to retrieve the correct list of R 2 tuples whose X 2 values match X 1 values. We can thus use X 1 values to form rings (see Chapters 6 and 7 of [26]) connecting each tuple of R 1 to the tuples of R 2 that it owns (ownership connection) or, that reference it (inverse reference connection) Since a same relation R can be at the origin of many manyto one connections (inverse ownership and reference connections) it can contain several foreign ....

G. Wiederhold. File Organization for Database Design. McGraw-Hill, 1987.

....database db, we search all the buckets whose address ends with h db (db) 6 . The hw hash function maps words into integers between 0 and 2 bw Gamma 1. Given a word w = a n . a 0 , hw does this mapping by first translating word w into integer i w = P n i=0 lettervalue(a i ) Theta 36 i [41], and then taking b(i w A mod 1)2 bw c, where A = 0:6180339887[22] Similarly, the h db hash function maps database numbers into integers between 0 and 2 b db Gamma 1. Given a database number i db , h db maps it into integer b(i db A mod 1)2 b db c. We initially assign one disk block per ....

Gio Wiederhold. File organization for database design. McGraw-Hill, 1987.

....database db, we search all the buckets whose address ends with h db (db) 6 . The hw hash function maps words into integers between 0 and 2 bw Gamma 1. Given a word w = a n : a 0 , hw does this mapping by first translating word w into integer i w = P n i=0 lettervalue(a i ) Theta 36 i [40], and then taking b(i w A mod 1)2 bw c, where A = 0:6180339887[22] Similarly, the h db hash function maps database numbers into integers between 0 and 2 b db Gamma 1. Given a database number i db , h db maps it into integer b(i db A mod 1)2 b db c. We initially assign one disk block per ....

Gio Wiederhold. File organization for database design. McGraw-Hill, 1987.

....mnemonic identifiers for subobject references, as in the examples above. The interested reader is referred to [16] for further discussion. 2.2 Related Models and Systems Labeled fields are used as the basis of several data models or data formatting conventions. For example, a tagged file system [19] uses labels instead of positions to identify fields; this is useful when records may have a large number of possible fields, but most fields are empty. Electronic mail messages consist of label value pairs (e.g. label From and value yannis cs.stanford.edu ) More recently, Lotus Notes [14] has ....

G. Wiederhold. File Organization for Database Design. McGraw Hill, New York, 1987.

....database db, we search all the buckets whose address ends with h db (db) 6 . The hw hash function maps words into integers between 0 and 2 bw Gamma 1. Given a word w = a n : a 0 , hw does this mapping by first translating word w into integer i w = P n i=0 lettervalue(a i ) Theta 36 i [46], and then taking b(i w A mod 1)2 bw c, where A = 0:6180339887[24] Similarly, the h db hash function maps database numbers into integers between 0 and 2 b db Gamma 1. Given a database number i db , h db maps it into integer b(i db A mod 1)2 b db c. We initially assign one disk block per ....

Gio Wiederhold. File organization for database design. McGraw-Hill, 1987.

....sources one often faces unstructured information whose form may change dynamically. Many applications that have to deal with such information use some type of self describing data model where each data item has an associated descriptive label. Applications include tagged file systems [Wie87] Lotus Notes [Mar93] the Teknekron Information Bus [O 93] LOOM frames [MY89] electronic mail, RFC1532 bibliographic records, and many more. For this reason we have selected a self describing model, in particular the Object Exchange Model (OEM) PGMW95] as the common data model exported ....

G. Wiederhold. File Organization for Database Design. McGraw Hill, New York, 1987.

....illustrate the power of MSL and of fusion based on semantic object identifiers. 2 The OEM Model Most applications that have to deal with semi structured information use a self describing model, where each data item has an associated descriptive label. Applications include tagged file systems [Wie87] Lotus NOTES [Mar93] the Teknekron s Information Bus [O 93] LOOM frames [MY89] electronic mail, RFC1532 bibliographic records, and many more. In [PGMW95] we have defined a self describing data model [MR87] called the Object Exchange Model (OEM) that captures the essential features of ....

G. Wiederhold. File Organization for Database Design. McGraw Hill, New York, 1987.

....and systems. We focus particularly on the differences between OEM and more conventional object oriented models, and we discuss the motivation behind our design of OEM. Labeled fields are used as the basis of several data models or data formatting conventions. For example, a tagged file system [20] uses labels instead of positions to identify fields; this is useful when records may have a large number of possible fields, but most fields are empty. Electronic mail messages consist of label value pairs (e.g. label From and value yannis cs.stanford.edu ) More recently, Lotus Notes [15] has ....

G. Wiederhold. File Organization for Database Design. McGraw Hill, New York, 1987.

....office i cmp 3 : hphoto, bits, some bits i where each cmp i is some mnemonic identifier for the subobject. We use this generic notation for examples throughout the remainder of this section. As mentioned in Section 1, self describing models have been used in many systems, including file systems [30], Lotus Notes [20] by Teknekron Software Systems [21] and for electronic mail. In many of these systems, nesting of objects is not allowed, so OEM can be viewed as a generalization of these models. OEM is simpler than conventional object models, but it does support the two key features required ....

G. Wiederhold. File Organization for Database Design. McGraw Hill, New York, 1987.

....some fixed set of methods for performing an operation in the plan tree. 6.3.3 Device scheduling The scheduler, in our framework, integrates the tasks of device scheduling and cache management. Hence, many device scheduling algorithms are relevant in our context. One class of algorithms [BK79, Wie87, Hof83, SLM93] deals with reordering a set of pending I O requests to reduce seek and rotational latency on magnetic disks. There is also work on scheduling a collection of I O requests on tape so as to reduce seek cost. For instance, KMP90] addresses the problem of finding the optimum execution ....

G. Wiederhold. File organization for database design. McGraw-Hill, New York, 1987.

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Wiederhold, G. "File Organization for Database Design," McGraw-Hill, 1987.

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Wiederhold, G. "File Organization for Database Design," McGraw-Hill, 1987.

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Wiederhold, G. "File Organization for Database Design," McGrawHill, 1987.

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Gio Wiederhold, File Organization for DataBase Design, McGraw Hill, 1987.

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Gio Wiederhold. File Organization for Database Design. Computer Science Series. McGraw-Hill, 1987. ISBN 0-07-070133-4.

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Gio Wiederhold. File Organization for Database Design. Computer Science Series. McGrawHill, 1987. ISBN 0-07-070133-4.

No context found.

G. Wiederhold, File Organization for Database Design. McGraw-Hill, 1987.

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