Title: Multimedia Database Schema Design
1Multimedia Database Schema Design
2Outline
- MMDB Design Issues
- Multimedia Data Types
- Features and Similarity Functions
- M-Dependencies
- Normalization
- Evaluation
3MMDB Design Issues
- Requirements for the MMDB
- Representation, storage, interpretation,
composition, retrieval and delivery of diverse
data types - Data Model
- Storage structure
- Architecture
- Retrieval algorithms
4MMDB Schema Design
- Building blocks
- Data type
- Relations
- Rows (tuples)
- Columns
- Similarity function and thresholds
- Dependencies
- MMDB schema
- Knobs
- Data types, relations, similarity functions,
thresholds
5Data Types
- Semantics of Multimedia Attributes
- Why not BLOB
- Generalized Icon
- (xm, xi)
- Earcons, ticons, micon, vicons
- multicons
6Features and Similarity Functions
- Features and Tuples comparison
- Equal vs. similar
- Similarity Functions
- Distance functions
- Threshold
- Combination of similarity functions
Let R(z1Z1,, znZn), v be a tuple distance
function on R, t be a maximum distance
threshold, x(x1,, xn) and y(y1,, yn) be two
tuples in R, we say that x is similar within t
to y with respect to v, denoted with x ?w(t) y,
iff v(x, y)? t.
7M-Dependencies
MFD Let R be a relation with attribute set U,
and X, Y ? U. Xg1(t) ? Yg2(t) is a type-M
functional dependency (MFD) relation if and only
if for any two tuples t1 and t2 in R that have
t1X ?g1(t) t2X, then t1Y ?g2(t) t2Y,
where g1?TD(X) and g2?TD(Y), whereas t and t ?
0,1 are thresholds.
- The benefits from exploiting dependencies
- Classes of M-Dependencies
- Type M Functional dependency (MFD)
- Type M Multivalued dependency (MMD)
- Type M Join dependency (MJD)
- technically
MMD Let R be a multimedia relation with
attribute set U, and X, Y ? U. Xg1(t') ?
Yg2(t'')g3(t''') is a type-M multivalued
dependency (MMD) relation if and only if for any
two tuples t1 and t2 in R such that t1X ?g1(t')
t2X, there also exist in R two tuples t3 and t4
with the following properties t3X, t4X ?
t1X?g1(t') t3Y ?g2(t'') t1Y and t4Y
?g2(t'') t2Y t3R (XY) ?g3(t''') t2R (XY)
and t4R (XY) ?g3(t''') t1R (XY). where
g1?TD(X), g2?TD(Y) and g3?TD(R(XY)), whereas t',
t'' and t''' ? 0,1 are thresholds.
MJD Let R be a relation on U, and X1,,Xn ? U,
with the union of Xis being U. If R
PX1,g1(t1)(R) ?g1(t1) PX2,g2(t2)(R)
?g2(t2)?gn-1(tn-1) PXn,I (R), we say that R
satisfies a Type-M Join Dependency (MJD), denoted
by ?g1(t1),, gn-1(tn-1)X1,..., Xn, where
gi?TD(Xi ? Xi1) and ti ? 0,1 for each 1 ? i ?
n-1.
8Normal Forms
1MNF We say that a multimedia database schema is
in first multimedia normal form (1MNF) if each
attribute A has the type of number, string or
elementary generalized icon.
- Dependency-based design practice
- Benefits
- Types of Normal Forms
- 1MNF
- 2MNF
- 3MNF
- 4MNF
- 5MNF
- technically
2MNF We say that a multimedia database schema is
in second multimedia normal form (2MNF) if it is
in 1MNF and each non prime attribute A is fully
dependent on the primary key.
3MNF We say that a multimedia database schema R
is in third multimedia normal form (3MNF) if it
is in 2MNF and the non prime attributes are not
mutually dependent.
4MNF We say that a multimedia database schema R
is in fourth multimedia normal form (4MNF) with
respect to a set of multimedia dependencies D if,
for every nontrivial MMD Xg1(t1) ?
Yg2(t2)g3(t3) in D, X is a superkey for R.
5MNF we say that R is in 5MNF with respect to a
set D of MFDs, MMDs, and MJDs if, for every
nontrivial type-M join dependency ?g1(t1),,
gn-1(tn-1)(X1,..., Xn) in D, every Xi is a
superkey for R.
9Term Project MMDB Refactoring
10Project Goal
- To implement an usable tool to enable automatic
database transformation - Improve the user interface
- Improve the algorithm