I
nte
rna
t
io
na
l J
o
urna
l o
f
E
lect
rica
l a
nd
Co
m
p
ute
r
E
ng
in
ee
ring
(
I
J
E
CE
)
Vo
l.
10
,
No
.
6
,
Dec
em
b
er
2
0
2
0
,
p
p
.
6
6
1
8
~
6
6
2
8
I
SS
N:
2
0
8
8
-
8708
,
DOI
: 1
0
.
1
1
5
9
1
/
i
j
ec
e
.
v
1
0
i
6
.
pp
6
6
1
8
-
6
6
2
8
6618
J
o
ur
na
l ho
m
ep
a
g
e
:
h
ttp
:
//ij
ec
e.
ia
esco
r
e.
co
m/in
d
ex
.
p
h
p
/I
JE
C
E
A
n
a
tive
en
ha
nce
d e
la
stic
e
x
tensio
n
t
a
bles
m
ul
ti
-
t
en
a
nt
da
taba
se
M
a
g
y
E
l Ba
nh
a
w
y
1
,
Wa
la
a
Sa
ber
2
,
F
a
t
hy
A
m
er
3
1,
2
De
p
a
rt
m
e
n
t
o
f
El
e
c
tri
c
a
l
En
g
in
e
e
rin
g
,
F
a
c
u
lt
y
o
f
En
g
in
e
e
rin
g
,
P
o
rt
S
a
i
d
Un
iv
e
rsity
,
Eg
y
p
t
3
De
p
a
rt
m
e
n
t
o
f
Co
m
p
u
ter S
c
ien
c
e
s,
F
a
c
u
lt
y
o
f
Co
m
p
u
ter an
d
I
n
f
o
rm
a
ti
o
n
S
c
ien
c
e
,
6
Oc
to
b
e
r
Un
iv
e
rsity
,
Eg
y
p
t
Art
icle
I
nfo
AB
ST
RAC
T
A
r
ticle
his
to
r
y:
R
ec
eiv
ed
A
p
r
10
,
2
0
20
R
ev
i
s
ed
Ma
y
2
9
,
2020
A
cc
ep
ted
J
u
n
6
,
2
0
2
0
M
u
lt
i
-
te
n
a
n
c
y
is
a
c
lo
u
d
c
o
m
p
u
t
in
g
se
rv
ice
th
a
t
e
n
a
b
les
m
u
lt
ip
le
c
u
sto
m
e
rs
to
sh
a
re
t
h
e
sa
m
e
so
f
t
wa
re
.
Th
e
in
ter
n
e
t
o
f
t
h
in
g
s
(I
o
T
)
is
b
a
se
d
o
n
d
istri
b
u
ti
n
g
d
e
v
ice
s
a
n
d
o
b
jec
ts
t
h
ro
u
g
h
th
e
i
n
tern
e
t
th
a
t
n
e
e
d
s
a
n
e
ffe
c
ti
v
e
m
u
lt
i
-
ten
a
n
t
sc
h
e
m
a
.
M
e
r
g
in
g
th
e
m
u
lt
i
-
ten
a
n
t
stru
c
t
u
re
w
it
h
Io
T
s
y
ste
m
s
b
e
c
o
m
e
s
m
o
re
c
h
a
ll
e
n
g
in
g
d
u
e
to
th
e
d
if
f
e
r
e
n
t
d
a
ta
t
y
p
e
s
o
f
Io
T
a
n
d
w
o
rk
lo
a
d
s.
T
h
e
re
is
a
n
e
e
d
to
h
a
n
d
le
a
m
a
s
siv
e
a
m
o
u
n
t
o
f
m
e
tad
a
ta
b
y
m
u
lt
i
-
ten
a
n
t
a
p
p
li
c
a
ti
o
n
s.
T
h
is
p
a
p
e
r
h
a
s
t
w
o
m
a
in
a
i
m
s
to
so
lv
e
th
is
p
ro
b
lem
.
F
irst,
it
p
r
o
p
o
se
s
a
n
e
n
h
a
n
c
e
d
e
las
ti
c
e
x
ten
sio
n
tab
les
(E
3
T
)
sc
h
e
m
a
to
q
u
e
ry
th
e
Io
T
d
a
tab
a
se
e
ff
ici
e
n
tl
y
.
S
e
c
o
n
d
,
it
p
ro
p
o
se
s
a
Hy
b
rid
m
u
lt
i
-
ten
a
n
t
d
a
tab
a
se
(NX
D
-
E
3
T
)
a
s
a
c
o
m
b
in
a
ti
o
n
o
f
th
e
E
3
T
a
n
d
Na
ti
v
e
X
M
L
Da
tab
a
se
to
re
d
u
c
e
th
e
re
sp
o
n
se
ti
m
e
a
n
d
su
p
p
o
rt
a
c
o
m
m
o
n
q
u
e
ry
lan
g
u
a
g
e
.
T
h
e
p
ro
p
o
se
d
sc
h
e
m
a
w
a
s
i
m
p
le
m
e
n
ted
o
n
a
n
Io
T
b
e
n
c
h
m
a
r
k
.
T
h
e
si
m
u
latio
n
re
su
lt
s
sh
o
w
t
h
a
t
th
e
p
ro
p
o
se
d
NX
D
-
E
3
T
o
u
tp
e
rf
o
rm
s
th
e
o
t
h
e
r
m
u
lt
i
-
ten
a
n
t
d
a
tab
a
se
s in
term
s o
f
th
e
q
u
e
ry
sp
e
e
d
.
K
ey
w
o
r
d
s
:
C
lo
u
d
c
o
m
p
u
tin
g
EET
I
o
T
Mu
lti
-
te
n
an
t
d
atab
ase
NXD
-
s
ch
e
m
a
Co
p
y
rig
h
t
©
2
0
2
0
In
stit
u
te o
f
A
d
v
a
n
c
e
d
E
n
g
i
n
e
e
rin
g
a
n
d
S
c
ien
c
e
.
Al
l
rig
h
ts re
se
rv
e
d
.
C
o
r
r
e
s
p
o
nd
ing
A
uth
o
r
:
Ma
g
y
E
l B
an
h
a
wy
,
Dep
ar
t
m
en
t o
f
E
lectr
ical
E
n
g
i
n
ee
r
in
g
,
P
o
r
t Said
Un
iv
er
s
it
y
,
P
o
r
t Said
,
E
g
y
p
t.
E
m
ail:
m
b
an
h
a
wy
2
0
0
4
@
g
m
ai
l.c
o
m
1.
I
NT
RO
D
UCT
I
O
N
Du
e
to
in
cr
ea
s
i
n
g
t
h
e
u
s
er
’
s
r
eq
u
ests
to
m
il
lio
n
s
o
f
o
n
li
n
e
u
s
er
s
,
o
r
g
an
izat
io
n
s
o
f
ten
s
p
en
d
lar
g
e
a
m
o
u
n
ts
o
f
t
h
eir
ti
m
e,
r
e
s
o
u
r
ce
s
a
n
d
co
s
t
in
th
e
ir
d
atab
ase
s
to
r
ed
,
to
en
s
u
r
e
th
a
t
t
h
e
co
r
r
ec
t
in
f
o
r
m
atio
n
i
s
av
ailab
le
w
h
e
n
it
is
r
eq
u
ir
ed
.
C
lo
u
d
co
m
p
u
tin
g
r
elies
o
n
s
h
ar
i
n
g
o
f
v
ar
io
u
s
r
eso
u
r
ce
s
s
u
c
h
as
n
et
w
o
r
k
s
,
s
er
v
er
s
,
s
to
r
ag
e,
ap
p
licatio
n
s
,
an
d
s
er
v
ices
to
ac
q
u
ir
e
co
h
er
en
ce
an
d
ec
o
n
o
m
ies
o
f
s
ca
le
[
1
]
.
T
h
ese
s
er
v
ices
ca
n
ac
co
m
p
li
s
h
i
n
m
an
y
f
o
r
m
s
s
u
ch
a
s
o
u
t
s
o
u
r
cin
g
,
o
n
-
d
e
m
an
d
r
eso
u
r
ce
p
r
o
v
is
io
n
,
t
h
e
ec
o
n
o
m
ics
o
f
s
ca
le,
an
d
p
ay
-
as
-
y
o
u
-
g
o
.
T
h
is
clo
u
d
s
o
f
t
w
ar
e
ap
p
r
o
ac
h
ed
is
ca
lled
s
o
f
t
w
ar
e
as
a
s
er
v
ice
(
SaaS)
.
SaaS
is
ca
p
ab
le
o
f
p
r
esen
tin
g
a
s
i
n
g
le
co
n
f
i
g
u
r
ab
le
s
o
f
t
w
ar
e
an
d
co
m
p
u
ti
n
g
en
v
ir
o
n
m
e
n
t
f
o
r
m
u
ltip
le
te
n
an
t
s
[
2
,
3]
.
SaaS
ap
p
licatio
n
s
ar
e
d
ep
lo
y
ed
a
s
h
o
s
ted
s
er
v
ices
a
n
d
ac
ce
s
s
e
d
f
r
o
m
e
v
er
y
w
h
er
e
o
v
er
t
h
e
w
eb
.
T
h
e
id
ea
o
f
o
u
ts
o
u
r
ci
n
g
s
o
f
t
w
ar
e
th
r
o
u
g
h
s
ev
er
al
ex
p
er
ie
n
ce
s
as i
n
[
4
]
.
Ma
n
y
co
m
p
a
n
ies
d
esire
to
o
u
ts
o
u
r
ce
th
eir
d
ata
to
a
th
ir
d
p
ar
t
y
w
h
ic
h
h
o
s
t
s
a
m
u
lti
-
te
n
a
n
t
d
atab
ase
s
y
s
te
m
to
p
r
o
v
id
e
t
h
e
d
ata
m
a
n
ag
e
m
e
n
t
s
er
v
ice
w
it
h
m
u
ch
f
e
w
er
r
eso
u
r
ce
s
,
t
h
r
o
u
g
h
t
h
e
s
a
m
e
s
er
v
er
i
n
s
tan
ce
.
T
h
e
m
ai
n
b
en
e
f
it
o
f
m
u
lti
-
te
n
an
c
y
i
s
to
m
in
i
m
ize
t
h
e
o
p
er
atin
g
co
s
t
s
o
f
r
u
n
n
i
n
g
s
o
f
t
w
ar
e
f
r
o
m
th
e
p
r
o
v
id
er
’
s
p
er
s
p
ec
tiv
e
[
5
]
.
Ma
n
y
p
r
o
b
le
m
s
ap
p
ea
r
ed
w
h
i
le
ac
h
iev
i
n
g
t
h
is
tar
g
et
s
u
c
h
a
s
lac
k
i
n
g
th
e
t
en
an
t
p
r
iv
ile
g
es
an
d
th
e
lo
n
g
ti
m
e
r
eq
u
ir
ed
to
p
er
f
o
r
m
a
s
in
g
le
q
u
er
y
.
T
h
er
ef
o
r
e
,
t
h
is
p
ap
er
p
r
o
p
o
s
e
d
a
n
ati
v
e
e
n
h
a
n
ce
d
ela
s
tic
e
x
ten
s
io
n
tab
les
d
atab
ase
(
NX
D
-
E
3
T
)
as
a
co
m
b
in
a
tio
n
o
f
t
h
e
p
r
o
p
o
s
e
d
E
3
T
s
ch
e
m
a
an
d
th
e
Nati
v
e
XM
L
d
ata
m
o
d
el
to
i
n
cr
ea
s
e
t
h
e
p
er
f
o
r
m
a
n
ce
b
y
co
m
p
u
ti
n
g
t
h
e
r
esp
o
n
s
e
t
i
m
e
s
o
f
th
e
p
r
ef
o
r
m
ed
q
u
er
y
.
A
p
p
lin
g
t
h
i
s
Sch
e
m
a
to
th
e
I
o
T
Sy
s
te
m
i
s
co
n
s
id
er
ed
an
ad
d
itio
n
al
co
n
tr
ib
u
t
io
n
in
th
is
p
ap
er
.
T
h
e
r
em
ain
d
er
o
f
th
is
p
ap
er
is
s
tr
u
ct
u
r
ed
as
f
o
l
lo
w
s
.
Sectio
n
2
r
ev
ie
w
s
th
e
b
ac
k
g
r
o
u
n
d
f
o
r
m
u
lti
-
te
n
an
c
y
m
ai
n
ap
p
r
o
ac
h
es
an
d
t
h
e
r
elate
d
w
o
r
k
o
f
m
u
lti
-
te
n
an
c
y
d
atab
as
e
tech
n
iq
u
es,
s
ec
tio
n
3
d
escr
i
b
es
th
e
p
r
o
p
o
s
ed
Sch
e
m
a
f
o
r
NXD
-
E
3
T
Mu
lti
-
T
en
an
t
Data
b
ase,
s
ec
tio
n
4
Evaluation Warning : The document was created with Spire.PDF for Python.
I
n
t J
E
lec
&
C
o
m
p
E
n
g
I
SS
N:
2
0
8
8
-
8708
A
n
a
tive
en
h
a
n
ce
d
ela
s
tic
ex
ten
s
io
n
ta
b
les mu
lti
-
ten
a
n
t
d
a
ta
b
a
s
e
(
Ma
g
y
E
l B
a
n
h
a
w
y)
6619
p
r
o
p
o
s
e
s
t
h
e
r
es
u
lt
s
f
o
r
t
h
e
p
e
r
f
o
r
m
an
c
e
o
f
o
u
r
p
r
o
p
o
s
ed
m
eth
o
d
.
Fi
n
all
y
,
s
ec
t
io
n
5
co
n
cl
u
d
es
t
h
i
s
p
ap
er
an
d
d
escr
ib
es f
u
t
u
r
e
w
o
r
k
.
2.
B
ACK
G
RO
UND
AN
D
RE
L
AT
E
D
WO
RK
S
2
.
1
.
B
a
ck
g
ro
un
d a
nd
ba
s
ic
s
co
ncept
Sin
ce
I
o
T
h
as
b
ec
o
m
e
m
o
r
e
s
ig
n
i
f
ica
n
t,
ad
d
itio
n
al
d
esig
n
s
m
u
s
t
b
e
p
r
ese
n
ted
ea
ch
d
ay
to
ad
ap
t
th
e
s
p
ec
i
f
icitie
s
in
tr
o
d
u
ce
d
b
y
th
e
s
e
s
y
s
te
m
s
o
f
th
e
p
h
y
s
ic
al
w
o
r
ld
an
d
th
e
p
u
b
lic
n
et
wo
r
k
s
[6
-
8]
.
So
m
e
o
f
th
ese
s
o
l
u
tio
n
s
b
ased
o
n
SaaS
an
d
Mu
lti
-
te
n
an
c
y
[
9
]
.
P
ay
in
g
th
e
m
u
lti
-
ten
a
n
c
y
m
o
d
els
b
as
ed
o
n
th
e
w
a
y
h
o
w
d
at
a
is
is
o
lated
f
o
r
i
n
d
iv
id
u
al
t
en
an
t
s
,
t
h
er
e
ar
e
th
r
ee
m
ain
ap
p
r
o
ac
h
es o
f
m
u
lt
i
-
ten
a
n
c
y
d
atab
ases
as s
h
o
w
n
i
n
Fig
u
r
e
an
d
i
n
[
1
0
]
.
Mu
lti
-
te
n
a
n
c
y
i
s
b
ased
o
n
S
h
ar
ed
DB
–
Sh
ar
ed
Sch
e
m
a
[
1
1
]
.
Mu
lti
-
te
n
an
c
y
i
s
ca
p
ab
le
o
f
s
er
v
i
n
g
a
lar
g
e
n
u
m
b
er
o
f
t
e
n
a
n
ts
w
i
th
a
m
i
n
i
m
u
m
g
en
er
al
c
o
s
t
[
1
2
]
.
Fig
u
r
e
1
.
A
p
p
r
o
ac
h
es to
m
a
n
a
g
in
g
m
u
lti
-
t
e
n
an
c
y
2
.
2
.
Rela
t
ed
w
o
rk
s
T
h
er
e
ar
e
m
a
n
y
tech
n
iq
u
e
s
s
u
b
m
it
ted
f
o
r
d
e
m
o
n
s
tr
a
tin
g
d
ata
in
m
u
lti
-
te
n
a
n
t
d
atab
ases
.
T
h
ese
tech
n
iq
u
e
s
ac
co
m
p
li
s
h
s
o
m
e
f
ea
t
u
r
es,
at
t
h
e
e
x
p
en
s
e
o
f
o
th
er
f
ea
t
u
r
es.
T
h
ese
tec
h
n
iq
u
e
s
ar
e
s
ti
ll
n
o
t
en
o
u
g
h
,
an
d
n
o
t
e
x
ce
ed
i
n
g
m
u
lti
-
te
n
an
t
d
atab
ase
c
h
alle
n
g
es.
So
m
e
o
f
th
e
s
e
tec
h
n
iq
u
es
ar
e
e
x
a
m
in
ed
in
th
e
f
o
llo
w
i
n
g
p
ar
ag
r
ap
h
s
.
P
r
iv
ate
T
a
b
les
[
1
3
]
tech
n
iq
u
e
p
er
m
it
s
ea
ch
te
n
an
t
to
p
o
s
s
es
s
h
i
s
p
r
iv
ate
tab
les
w
h
ic
h
ca
n
b
e
d
if
f
er
e
n
t
an
d
ex
p
an
d
ed
.
T
h
e
q
u
er
y
is
p
r
o
ce
s
s
ed
b
y
d
atab
ase
w
it
h
o
u
t
u
s
i
n
g
ex
tr
a
co
lu
m
n
s
lik
e
“ten
a
n
t_
id
”
to
d
is
tin
g
u
is
h
a
n
d
is
o
late
te
n
an
t
’
s
d
ata,
as
s
u
b
m
itted
in
th
is
p
ap
er
f
o
r
th
e
r
est
o
f
th
e
m
u
l
ti
-
te
n
a
n
t
d
atab
as
e
s
ch
e
m
a
m
ap
p
in
g
tec
h
n
iq
u
e
s
[
1
4
]
.
T
h
e
ex
ten
s
io
n
tab
les
ar
e
s
i
m
u
lated
d
u
e
to
th
e
d
ev
elo
p
m
e
n
t
o
f
th
e
d
ec
o
m
p
o
s
ed
s
to
r
ag
e
m
o
d
el
t
h
at
h
ad
b
ee
n
r
eq
u
ir
ed
d
escr
ib
ed
i
n
[
1
5
]
.
T
h
is
tech
n
iq
u
e
co
n
s
i
s
t
s
o
f
cr
ea
tin
g
s
e
g
m
e
n
t
s
o
f
a
ta
b
le
o
f
n
-
co
lu
m
n
s
in
to
n
2
-
c
o
l
u
m
n
tab
les.
T
h
i
s
tech
n
iq
u
e
o
f
u
s
i
n
g
E
x
ten
s
io
n
T
ab
les
is
co
n
s
id
er
ed
o
u
ts
ta
n
d
in
g
to
t
h
e
P
r
iv
ate
T
ab
les ap
p
r
o
ac
h
d
escr
ib
ed
ab
o
v
e.
Mu
ltip
le
te
n
an
ts
ca
n
u
s
e
t
h
e
b
ase
tab
les also
t
h
e
ex
te
n
s
i
o
n
tab
les.
T
h
e
Un
iv
er
s
al
T
ab
le
as
p
r
ese
n
ted
in
[
1
6
]
a
s
p
a
r
s
e
d
ataset
co
n
s
is
ts
o
f
a
h
u
g
e
n
u
m
b
er
o
f
co
lu
m
n
s
.
T
h
e
Un
iv
er
s
al
T
ab
le
is
a
tab
l
e
th
at
co
n
tai
n
s
ex
tr
a
co
lu
m
n
s
o
f
th
e
b
asics
ap
p
licatio
n
s
c
h
e
m
a
co
lu
m
n
s
,
w
h
ic
h
p
er
m
i
ts
te
n
a
n
ts
to
s
to
r
e
t
h
eir
n
ee
d
ed
co
lu
m
n
s
s
id
e
b
y
s
id
e.
Sto
r
in
g
s
u
c
h
a
d
ata
s
et
ca
n
p
o
ten
tiall
y
lo
w
er
it
s
p
er
f
o
r
m
a
n
ce
d
u
e
to
t
h
e
h
i
g
h
n
u
m
b
er
o
f
NU
L
L
v
al
u
es it
m
a
y
co
n
tain
.
I
n
P
iv
o
t
T
a
b
les
,
ea
ch
co
lu
m
n
o
f
ea
ch
r
o
w
i
n
a
lo
g
ical
s
o
u
r
ce
tab
le
is
co
n
v
er
ted
to
its
r
ec
o
r
d
in
th
e
P
iv
o
t
T
ab
le
[3
,
1
6
]
.
T
h
e
r
o
w
s
in
t
h
e
P
iv
o
t
T
ab
le
r
ep
r
e
s
en
ted
b
y
f
o
u
r
co
lu
m
n
s
:
‘
te
n
an
t_
id
’
,
‘
tab
le_
id
’
,
‘
co
l’
,
an
d
‘
r
o
w
’
w
h
ic
h
ar
e
u
s
ed
to
id
en
tify
ea
ch
r
o
w
i
n
th
e
lo
g
ical
s
o
u
r
ce
tab
le.
T
h
e
s
elec
ted
d
ata
ty
p
es
a
r
e
Evaluation Warning : The document was created with Spire.PDF for Python.
I
SS
N
:
2
0
8
8
-
8708
I
n
t J
E
lec
&
C
o
m
p
E
n
g
,
Vo
l.
10
,
No
.
6
,
Dec
em
b
er
2
0
2
0
:
6
6
1
8
-
6
6
2
8
6620
elastic
d
ata
t
y
p
es
s
u
ch
a
s
V
AR
C
H
AR
to
in
cr
ea
s
e
t
h
e
p
o
s
s
i
b
ilit
y
o
f
o
th
er
d
if
f
er
en
t
d
ata
ty
p
e
s
th
at
ca
n
b
e
ca
s
t
to
.
Fo
r
ex
a
m
p
le,
th
e
“
p
i
v
o
t_
s
tr
”
tab
le
ca
n
b
e
u
s
ed
to
s
to
r
e
n
o
n
-
n
u
m
er
ical
d
ata
t
y
p
e
s
.
A
n
d
“
p
iv
o
t_
in
t”
tab
le
w
h
ic
h
is
u
s
ed
to
s
to
r
e
th
e
n
u
m
er
ica
l d
ata
ty
p
e
v
a
lu
e
s
.
T
h
e
C
h
u
n
k
T
ab
le
is
an
o
th
er
s
tr
u
ctu
r
e
tech
n
iq
u
e
th
at
is
clo
s
est
to
th
e
P
iv
o
t
T
ab
le
tech
n
iq
u
e
[
4
]
.
E
x
ce
p
t,
it
co
n
tain
s
a
g
r
o
u
p
o
f
d
ata
co
lu
m
n
s
w
ith
a
m
ix
tu
r
e
o
f
d
ata
ty
p
es
th
at
ar
e
p
lace
d
th
e
co
lu
m
n
‘
co
l’
in
th
e
P
iv
o
t
T
ab
le
w
ith
th
e
‘
ch
u
n
k
’
co
lu
m
n
in
th
e
C
h
u
n
k
T
ab
le.
T
h
is
tech
n
iq
u
e
s
p
lits
th
e
lo
g
ical
s
o
u
r
ce
tab
le
i
n
to
g
r
o
u
p
s
o
f
co
lu
m
n
s
.
E
ac
h
g
r
o
u
p
ap
p
o
in
ted
to
a
u
n
iq
u
e
C
hunk
-
I
D
an
d
co
n
v
er
ted
in
to
a
s
u
itab
le
C
h
u
n
k
T
ab
le
[
1
7
]
.
T
h
e
C
h
u
n
k
Fo
ld
in
g
tech
n
iq
u
e
is
d
er
iv
ed
f
r
o
m
th
e
C
h
u
n
k
T
ab
le
tech
n
iq
u
e
an
d
th
e
E
x
ten
s
io
n
T
ab
les
as
p
r
esen
ted
in
[1
,
13]
.
T
h
is
s
ch
em
a
v
er
tically
s
eg
m
en
ted
v
ir
tu
al
tab
le
s
in
to
ch
u
n
k
s
.
E
ac
h
s
eg
m
en
t
h
as
a
‘
ch
u
n
k
_
id
’
w
h
er
e
a
ch
u
n
k
o
f
co
lu
m
n
s
is
p
ar
titi
o
n
ed
in
to
s
eg
m
en
ts
o
f
co
lu
m
n
s
.
T
h
e
r
em
ain
in
g
p
ar
ts
ar
e
m
ap
p
ed
in
to
th
e
ex
ten
s
io
n
s
.
B
u
t
it
ca
n
b
e
im
p
lem
en
ted
in
o
p
en
-
s
o
u
r
ce
r
elatio
n
al
d
atab
ase
p
r
o
d
u
cts
s
u
ch
as P
o
s
tg
r
eSQL
.
T
h
e
XM
L
T
ab
le
d
atab
ase
ex
ten
s
io
n
tech
n
iq
u
e
is
co
n
s
tr
u
cted
b
y
ex
ten
s
ib
le
m
ar
k
u
p
lan
g
u
ag
e
(
XM
L
)
[
1
8
,
19]
.
T
h
is
is
ac
co
m
p
lis
h
ed
b
y
p
r
o
v
id
in
g
an
XM
L
d
ata
ty
p
e
o
r
b
y
ad
d
in
g
th
e
XM
L
d
o
cu
m
en
t
in
to
th
e
d
atab
ase
as
a
L
ar
g
e
Ob
j
ec
t.
Ner
v
eless
,
th
is
tech
n
iq
u
e
r
ed
u
ce
s
th
e
o
v
er
all
p
er
f
o
r
m
an
ce
u
s
in
g
XM
L
f
iles
d
u
e
to
it c
o
n
s
u
m
e
s
lar
g
e
s
p
ac
e
o
f
th
e
R
A
M.
T
h
e
E
last
ic
E
x
ten
s
io
n
T
ab
les
d
atab
ase
tech
n
iq
u
e
w
h
ich
is
th
e
m
o
s
t
r
ec
en
t
tech
n
iq
u
e
o
f
d
esig
n
i
ng
an
d
s
tr
u
ctu
r
in
g
a
m
u
ltit
en
an
t
d
atab
ase
[
1
3
,
14]
.
E
E
T
is
a
d
atab
ase
tech
n
iq
u
e
th
at
u
s
es
th
e
Sh
ar
ed
DB
–
Sh
ar
ed
Sch
em
a
m
o
d
el.
EET
is
co
n
s
is
ts
o
f
th
r
ee
m
ain
cla
s
s
es:
co
m
m
o
n
ten
an
t
tab
les
(
C
T
T
)
,
v
ir
tu
al
ex
ten
s
io
n
tab
les
(
VE
T
)
,
an
d
elastic
ex
ten
s
io
n
tab
les
(
E
E
T
)
.
T
h
e
f
ir
s
t
class
is
th
e
C
T
T
th
at
ca
n
b
e
p
er
f
o
r
m
ed
on
an
y
b
u
s
in
ess
d
o
m
ain
d
atab
ase.
T
h
e
s
ec
o
n
d
class
is
th
e
VE
T
th
at
g
r
an
t
s
ten
an
ts
th
e
ab
ilit
y
to
ex
ten
d
th
e
ex
is
tin
g
b
u
s
in
ess
d
atab
ase.
T
h
e
th
ir
d
class
is
elastic
ex
ten
s
io
n
tab
les
(
E
E
T
)
,
w
h
ich
co
n
s
is
ts
o
f
eig
h
t
tab
les
th
at
ar
e
u
s
ed
to
co
n
s
tr
u
ct
VE
T
s
tab
les
as
p
r
esen
ted
in
T
ab
le
1
.
E
E
T
ex
h
ib
its
a
f
lex
ib
le
m
eth
o
d
f
o
r
co
n
s
tr
u
ctin
g
th
e
ten
an
ts
’
d
atab
ase
s
ch
em
a.
W
ith
all
th
e
E
E
T
f
ea
tu
r
es
an
d
ad
v
an
tag
es,
it
h
as
s
o
m
e
d
r
aw
b
ac
k
s
s
u
ch
as
th
e
ac
ce
s
s
tim
e
to
lar
g
e
n
u
m
b
er
s
o
f
r
ec
o
r
d
s
th
er
e
w
ill
b
e
a
n
o
ticea
b
le
d
elay
d
u
e
to
th
e
u
s
ag
e
o
n
ly
o
f
th
e
r
elatio
n
al
d
ata
s
y
s
tem
.
T
h
e
E
E
T
is
lack
in
g
th
e
ten
an
t
p
r
iv
ileg
es
to
co
o
p
er
atin
g
w
ith
all
d
atab
ase
p
r
o
g
r
am
m
in
g
f
ea
tu
r
es
r
eq
u
ir
ed
n
o
w
ad
ay
s
s
u
ch
as tr
ig
g
er
s
,
r
o
u
tin
es,
an
d
p
r
o
ce
d
u
r
es.
T
ab
le
1
.
E
last
ic
e
x
ten
s
io
n
t
ab
l
es
N
o
.
T
a
b
l
e
N
a
me
T
a
b
l
e
F
e
a
t
u
r
e
s
1
“
d
b
_
t
a
b
l
e
”
En
a
b
l
e
t
e
n
a
n
t
s
t
o
c
r
e
a
t
e
v
i
r
t
u
a
l
t
a
b
l
e
s,
g
i
v
e
t
h
e
m
u
n
i
q
u
e
n
a
me
s
a
n
d
d
e
t
e
r
mi
n
e
t
h
e
n
u
mb
e
r
o
f
c
o
l
u
mn
s o
f
e
a
c
h
t
e
n
a
n
t
t
a
b
l
e
.
2
“
t
a
b
l
e
_
c
o
l
u
m
n
”
A
l
l
o
w
t
e
n
a
n
t
s
t
o
c
r
e
a
t
e
v
i
r
t
u
a
l
c
o
l
u
mn
s o
f
t
h
e
p
r
e
v
i
o
u
sl
y
c
r
e
a
t
e
d
“
d
b
_
t
a
b
l
e
”
t
a
b
l
e
s.
3
“
t
a
b
l
e
_
r
o
w
”
T
h
e
R
o
w
El
a
st
i
c
Ex
t
e
n
si
o
n
T
a
b
l
e
s
st
o
r
e
r
e
c
o
r
d
s
o
f
t
h
e
V
i
r
t
u
a
l
Ex
t
e
n
s
i
o
n
C
o
l
u
mn
s
w
h
i
c
h
t
e
n
a
n
t
c
r
e
a
t
e
d
i
n
t
h
r
e
e
se
p
a
r
a
t
e
d
i
s
t
i
n
g
u
i
s
h
t
a
b
l
e
s.
T
h
e
s
e
t
a
b
l
e
s
a
r
e
se
p
a
r
a
t
e
d
b
a
se
d
o
n
t
h
e
d
a
t
a
t
y
p
e
o
f
v
a
l
u
e
s.
-
“
t
a
b
l
e
_
r
o
w
”
t
a
b
l
e
i
s
u
t
i
l
i
z
e
d
f
o
r
st
o
r
i
n
g
v
a
l
u
e
s
l
i
k
e
I
N
T
,
F
L
O
A
T
,
D
A
T
E,
TI
M
ES
TA
M
P
,
TI
M
E,
C
H
A
R
,
V
A
R
C
H
A
R
a
n
d
B
O
O
L
E
A
N
.
-
“
t
a
b
l
e
_
r
o
w
_
b
l
o
b
”
t
a
b
l
e
i
s
u
t
i
l
i
z
e
d
f
o
r
st
o
r
i
n
g
l
a
r
g
e
d
a
t
a
v
a
l
u
e
s
s
u
c
h
a
s
t
h
e
B
L
O
B
v
a
l
u
e
s
f
o
r
v
i
r
t
u
a
l
c
o
l
u
m
n
s w
i
t
h
t
h
e
B
L
O
B
d
a
t
a
t
y
p
e
.
-
“
t
a
b
l
e
_
r
o
w
_
c
l
o
b
”
t
a
b
l
e
i
s
u
t
i
l
i
z
e
d
f
o
r
st
o
r
i
n
g
a
l
l
C
L
O
B
v
a
l
u
e
s fo
r
v
i
r
t
u
a
l
c
o
l
u
mn
s.
4
“
t
a
b
l
e
_
r
o
w
_
b
l
o
b
”
5
“
t
a
b
l
e
_
r
o
w
_
c
l
o
b
”
6
“
t
a
b
l
e
_
r
e
l
a
t
i
o
n
s
h
i
p
”
U
t
i
l
i
z
e
s t
e
n
a
n
t
s
t
o
c
r
e
a
t
e
v
i
r
t
u
a
l
r
e
l
a
t
i
o
n
sh
i
p
s
f
o
r
t
h
e
i
r
v
i
r
t
u
a
l
t
a
b
l
e
s.
7
“
t
a
b
l
e
_
i
n
d
e
x
”
A
p
p
l
i
e
d
t
o
a
d
d
a
n
d
c
r
e
a
t
e
v
i
r
t
u
a
l
i
n
d
e
x
e
s
t
o
v
i
r
t
u
a
l
c
o
l
u
mn
s
t
o
i
mp
r
o
v
e
t
h
e
sp
e
e
d
a
n
d
t
h
e
p
e
r
f
o
r
man
c
e
.
8
“
t
a
b
l
e
_
p
r
i
mary
_
k
e
y
_
c
o
l
u
mn
”
En
a
b
l
e
t
e
n
a
n
t
s
t
o
c
r
e
a
t
e
v
i
r
t
u
a
l
p
r
i
m
a
r
y
k
e
y
s
f
o
r
t
h
e
v
i
r
t
u
a
l
e
x
t
e
n
si
o
n
c
o
l
u
mn
s
w
h
i
c
h
a
r
e
st
o
r
e
d
i
n
t
h
e
“
t
a
b
l
e
_
c
o
l
u
mn
"
t
a
b
l
e
.
A
ll
th
e
p
r
ev
io
u
s
tech
n
iq
u
es
d
id
n
o
t
co
n
s
id
er
th
e
h
eter
o
g
en
eity
o
f
d
ata.
On
e
o
f
th
e
m
aj
o
r
ch
allen
g
es
is
h
o
w
to
h
an
d
le
an
in
cr
ea
s
in
g
am
o
u
n
t
o
f
h
eter
o
g
en
eo
u
s
I
o
T
d
ata
w
ith
a
v
ar
iety
o
f
d
ata
ty
p
es
an
d
d
ata
s
o
u
r
ce
s
.
Desp
ite
th
e
p
o
p
u
lar
ity
o
f
r
elatio
n
al
d
atab
ases
,
th
e
s
ca
lab
ilit
y
o
f
th
e
No
SQL
d
atab
ase
m
o
d
el
an
d
th
e
d
o
cu
m
en
t
-
ce
n
tr
ic
d
ata
s
tr
u
ctu
r
e
o
f
NXD
d
atab
ases
ap
p
ea
r
to
b
e
p
r
o
m
is
in
g
f
ea
tu
r
es
f
o
r
an
ef
f
icien
t
I
o
T
s
y
s
tem
[
2
0
]
.
T
h
e
r
esu
lt
s
in
[
2
1
]
s
h
o
w
th
at
th
e
No
SQL
d
atab
ase
is
th
e
b
est
ch
o
ice
f
o
r
q
u
er
y
s
p
ee
d
,
w
h
er
ea
s
NXD
is
ad
v
an
tag
eo
u
s
in
ter
m
s
o
f
f
lex
ib
ilit
y
an
d
ex
ten
s
ib
ilit
y
,
w
h
ich
ar
e
ess
en
tial
to
co
o
p
er
ate
w
ith
th
e
ch
ar
ac
ter
is
tics
o
f
I
o
T
d
ata.
T
h
e
ch
ar
ac
ter
is
tics
an
d
lim
itatio
n
s
o
f
th
e
p
r
ev
io
u
s
ly
d
escr
ib
ed
tech
n
iq
u
es
ar
e
ex
p
lain
ed
in
T
ab
le
2
.
I
n
th
is
p
ap
er
,
a
n
ew
m
u
lti
-
ten
an
t
d
atab
ase
s
ch
em
a
NXD
-
E
3
T
is
p
r
o
p
o
s
ed
th
at
co
m
b
in
es
a
n
ew
p
r
o
p
o
s
ed
E
3
T
s
ch
em
a
an
d
th
e
Nativ
e
XM
L
Data
b
ase
to
im
p
le
m
en
t
th
e
d
atab
ase
q
u
er
y
m
o
r
e
ef
f
icien
tly
an
d
r
ed
u
ce
th
e
q
u
er
y
r
esp
o
n
s
e
tim
e
[
2
2
]
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
n
t J
E
lec
&
C
o
m
p
E
n
g
I
SS
N:
2
0
8
8
-
8708
A
n
a
tive
en
h
a
n
ce
d
ela
s
tic
ex
ten
s
io
n
ta
b
les mu
lti
-
ten
a
n
t
d
a
ta
b
a
s
e
(
Ma
g
y
E
l B
a
n
h
a
w
y)
6621
T
ab
le
2
.
Mu
lti
-
te
n
an
c
y
t
ec
h
n
i
q
u
es c
h
ar
ac
ter
is
tics
N
o
.
M
u
l
t
i
-
t
e
n
a
n
c
y
D
a
t
a
b
a
s
e
D
e
s
i
g
n
Ex
t
r
a
C
o
l
u
m
n
s
La
r
g
e
N
o
.
o
f
Te
n
a
n
t
s
D
i
v
i
d
e
T
a
b
l
e
s
N
U
LL
v
a
l
u
e
s
O
v
e
r
h
e
a
d
C
o
m
p
l
e
x
i
t
y
Q
u
e
r
y
S
c
h
e
ma
K
n
o
w
n
i
n
A
d
v
a
n
c
e
La
r
g
e
S
p
a
c
e
o
f
t
h
e
R
A
M
N
o
t
i
c
e
a
b
l
e
d
e
l
a
y
P
r
o
g
r
a
m
mi
n
g
F
e
a
t
u
r
e
s
I
o
T
B
e
n
c
h
mar
k
1
P
r
i
v
a
t
e
T
a
b
l
e
s
2
T
h
e
e
x
t
e
n
si
o
n
t
a
b
l
e
s
3
T
h
e
U
n
i
v
e
r
sal
T
a
b
l
e
4
P
i
v
o
t
T
a
b
l
e
s
5
T
h
e
C
h
u
n
k
T
a
b
l
e
6
C
h
u
n
k
F
o
l
d
i
n
g
7
T
h
e
X
M
L
T
a
b
l
e
8
T
h
e
EET
T
e
c
h
n
i
q
u
e
3.
T
H
E
P
RO
P
O
S
E
D
NA
T
I
V
E
E
NH
ANCE
D
E
L
A
ST
I
C
E
X
T
E
N
SI
O
N
T
AB
L
E
S
DATAB
AS
E
(
NXD
-
E
3
T)
T
h
is
p
ap
er
p
r
o
p
o
s
es
a
m
u
lti
-
t
en
an
t
d
atab
ase
N
XD
-
E
3
T
s
ch
e
m
a
to
r
ed
u
ce
t
h
e
q
u
er
y
r
esp
o
n
s
e
t
i
m
e
in
cl
u
d
ed
p
r
o
g
r
am
m
i
n
g
f
ea
tu
r
e
s
w
it
h
a
s
i
m
p
le
a
n
d
f
i
x
ed
n
u
m
b
er
o
f
b
asic ta
b
les
.
T
h
e
co
n
tr
ib
u
tio
n
o
f
th
i
s
p
ap
er
co
n
s
is
ts
o
f
t
w
o
m
ai
n
p
ar
titi
o
n
s
:
First,
allo
w
i
n
g
ten
a
n
t
s
to
estab
lis
h
th
e
ir
f
u
ll
d
atab
ase
s
u
s
i
n
g
th
e
p
r
o
p
o
s
ed
en
h
a
n
ce
d
elastic e
x
te
n
s
io
n
tab
les
(E
3
T
)
an
d
ev
en
p
r
o
v
id
in
g
a
ll p
r
o
g
r
a
m
m
in
g
f
ea
tu
r
e
s
r
eq
u
i
r
ed
.
T
h
ese
f
ea
t
u
r
es
s
tar
ted
f
r
o
m
in
s
er
t,
u
p
d
ate,
a
n
d
d
elete
d
ata
to
ad
d
tr
ig
g
er
s
,
r
o
u
tin
es,
an
d
p
r
o
ce
d
u
r
es.
P
er
f
o
r
m
i
n
g
th
e
E
3
T
s
ch
e
m
a
p
r
o
v
id
es
a
v
ailab
ilit
y
as
th
is
d
esi
g
n
s
er
v
es
m
u
ltip
le
ten
a
n
ts
w
it
h
th
e
ir
s
u
b
-
u
s
er
s
.
T
h
en
,
ap
p
ly
in
g
t
h
i
s
n
e
w
s
tr
u
ct
u
r
e
o
f
d
atab
ase
o
n
I
o
T
b
en
ch
m
ar
k
[
2
3
]
.
Seco
n
d
,
it
p
r
o
p
o
s
es
th
e
NXD
-
E
3
T
s
ch
e
m
a
t
h
at
s
tr
u
c
tu
r
es
d
ata
f
o
r
s
h
ar
in
g
a
n
d
s
u
p
p
o
r
t
in
r
elatio
n
al
d
atab
ases
,
d
em
o
n
s
tr
ates
t
h
e
id
ea
o
f
ex
ec
u
ti
n
g
as
m
u
lti
-
ten
a
n
t
s
to
r
ag
e.
T
h
ese
o
b
j
ec
tiv
es
ar
e
th
e
m
o
ti
v
atio
n
to
p
r
o
p
o
s
e
an
i
m
p
r
o
v
ed
d
atab
ase
d
esig
n
E
3
T
s
ch
e
m
a
to
s
u
p
p
o
r
t
m
u
ltip
le
lev
e
ls
o
f
d
ata
is
o
latio
n
an
d
p
er
f
o
r
m
a
n
ce
f
o
r
all
te
n
a
n
ts
i
n
t
h
e
m
u
lti
-
te
n
a
n
t d
atab
ase.
3.
1
.
T
he
pro
po
s
ed
en
ha
nced
ela
s
t
ic
ex
t
ens
io
n t
a
bles
(E
3
T
)
s
che
m
a
T
h
e
E
3
T
d
atab
ase
s
ch
e
m
a
p
r
o
p
o
s
es a
n
en
h
a
n
ce
d
d
esig
n
o
f
m
u
lti
-
te
n
an
t
d
atab
ase
s
c
h
e
m
a
to
eli
m
i
n
ate
th
e
m
i
s
s
s
e
lecti
n
g
o
f
a
lar
g
e
s
ca
le
o
f
h
eter
o
g
e
n
eo
u
s
I
o
T
d
ata
f
r
o
m
th
e
d
atab
ase
an
d
p
er
m
its
a
n
y
te
n
an
t
to
h
an
d
le
t
h
e
d
atab
ase
q
u
er
ies
(
in
s
er
t,
u
p
d
ate,
d
elete
)
co
r
r
e
ctl
y
[
2
4
]
.
T
h
e
E
3
T
s
ch
e
m
a
h
an
d
le
s
th
e
d
ata
as
f
o
llo
w
s
:
3
.
1
.
1
.
Sto
ring
t
he
da
t
a
ba
s
ed
o
n t
ena
nt
a
ct
io
n
T
h
e
p
r
o
p
o
s
ed
d
esig
n
ad
d
s
t
h
r
ee
tab
les
to
th
e
E
last
ic
E
x
ten
s
io
n
T
ab
les
to
en
s
u
r
e
th
a
t
t
h
e
t
en
an
t
h
as
f
u
ll
p
r
o
g
r
a
m
i
n
g
co
n
tr
o
l
to
t
h
eir
d
atab
as
e
.
I
t
p
r
o
v
id
es
th
r
e
e
tab
les
to
s
o
lv
e
th
r
ee
d
i
f
f
er
en
t
ca
s
e
s
f
o
r
I
o
T
s
y
s
te
m
s
[
1
4
]
.
a.
“
tab
le_
tr
ig
g
er
”
tab
le,
th
is
tab
l
e
allo
w
s
te
n
an
t
s
to
ad
d
t
r
ig
g
e
r
s
,
it
is
ass
o
ciate
d
w
it
h
a
s
p
ec
if
ic
tab
le
th
at
ac
tiv
ate
s
w
h
en
a
s
p
ec
i
f
ic
e
v
en
t o
cc
u
r
s
f
o
r
th
a
t ta
b
le.
T
h
is
i
s
n
ee
d
ed
if
a
ten
a
n
t r
eq
u
ir
es to
t
r
ig
g
er
a
n
ac
tio
n
th
at
ac
ti
v
ates
w
h
e
n
a
s
p
ec
if
ic
ev
en
t o
cc
u
r
s
[
2
5
]
.
b.
“
tab
le_
p
r
o
ce
d
u
r
e”
tab
le,
th
i
s
t
ab
le
is
u
s
ed
w
h
e
n
it
is
r
eq
u
ir
ed
to
p
er
f
o
r
m
i
n
a
s
i
n
g
le
ca
ll
to
a
p
r
o
ce
d
u
r
e
a
r
ep
etitiv
e
tas
k
t
h
at
r
eq
u
ir
es
ch
ec
k
i
n
g
,
lo
o
p
in
g
,
m
u
ltip
le
s
t
ate
m
e
n
ts
o
n
th
e
s
er
v
er
w
it
h
a
r
etu
r
n
v
al
u
e
th
at
ca
n
b
e
s
to
r
ed
to
s
tar
t
m
a
n
y
a
n
o
th
er
ac
t
io
n
s
.
T
h
i
s
i
s
n
ee
d
ed
if
a
te
n
an
t
i
n
te
n
d
s
to
p
er
f
o
r
m
a
p
r
o
ce
d
u
r
e
as
a
r
esu
lt o
f
s
p
ec
if
ic
d
ata
.
c.
“
tab
le_
r
o
u
ti
n
e”
tab
le,
th
is
ta
b
le
p
er
m
its
te
n
a
n
ts
to
cr
ea
te
r
o
u
tin
es
f
o
r
p
r
ev
en
tin
g
t
h
e
n
ee
d
to
k
ee
p
r
eiss
u
in
g
th
e
i
n
d
iv
id
u
al
s
tat
e
m
en
ts
b
u
t
ca
n
r
ef
er
to
th
e
s
to
r
ed
r
o
u
tin
e
in
s
tead
w
h
ile
ac
ce
s
s
in
g
th
e
VE
T
o
r
C
T
T
[
2
6
]
.
T
h
is
is
n
ee
d
ed
wh
en
a
te
n
a
n
t
atte
n
d
s
to
cr
ea
t
e
a
r
o
u
tin
e
w
h
ic
h
ess
e
n
tia
ll
y
u
s
ed
to
g
at
h
er
p
ar
am
eter
s
an
d
co
m
p
ar
e
v
al
u
e
s
f
o
llo
w
i
n
g
b
y
s
i
n
g
le
r
et
u
r
n
v
a
lu
e
.
3
.
1
.
2
.
Sto
ring
t
he
da
t
a
ba
s
ed
o
n da
t
a
s
ize
a
nd
f
o
r
m
a
t
Data
in
I
o
T
s
y
s
te
m
s
ca
n
b
e
in
s
e
v
er
al
d
if
f
er
en
t
f
o
r
m
at
s
,
r
an
g
i
n
g
f
r
o
m
tex
t
an
d
n
u
m
b
er
s
to
au
d
io
,
p
ictu
r
es,
a
n
d
v
id
eo
s
.
T
h
e
p
r
o
p
o
s
ed
E
3
T
d
atab
ase
allo
w
s
th
e
u
s
er
to
s
to
r
e
d
if
f
er
en
t d
ata
t
y
p
es i
n
t
h
r
ee
d
if
f
er
e
n
t
s
ep
ar
ated
tab
les
[
2
7
]
`
.
a.
“
tab
le_
r
o
w
”
tab
le
,
f
o
r
s
to
r
i
n
g
s
m
all
d
ata
t
y
p
e
s
v
al
u
es
s
u
ch
as
(
C
H
AR
,
V
AR
C
H
A
R
,
I
NT
,
FL
O
A
T
,
DA
T
E
,
T
I
ME
).
Evaluation Warning : The document was created with Spire.PDF for Python.
I
SS
N
:
2
0
8
8
-
8708
I
n
t J
E
lec
&
C
o
m
p
E
n
g
,
Vo
l.
10
,
No
.
6
,
Dec
em
b
er
2
0
2
0
:
6
6
1
8
-
6
6
2
8
6
622
b.
“
tab
le_
r
o
w
_
b
lo
b
”
tab
le
,
f
o
r
s
to
r
in
g
m
u
lt
i
m
ed
ia
f
ile
s
.
I
t
s
to
r
es
th
e
d
ata
in
t
h
e
f
o
r
m
o
f
a
b
in
ar
y
lar
g
e
o
b
j
ec
t
(
B
L
OB
)
d
ata
ty
p
e.
c.
“
tab
le_
r
o
w
_
clo
b
”
tab
le,
f
o
r
s
t
o
r
in
g
i
m
a
g
e
f
i
les.
I
t
s
to
r
es
t
h
e
d
ata
in
th
e
f
o
r
m
o
f
a
ch
ar
a
cter
lar
g
e
o
b
j
ec
t
(
C
L
OB
)
d
ata
t
y
p
e.
3
.
1
.
3
.
Sto
ring
t
he
da
t
a
ba
s
ed
o
n t
he
qu
er
y
t
y
pe
I
n
th
e
E
3
T
s
ch
e
m
a,
th
e
d
atab
ase
tab
les ar
e
p
ar
titi
o
n
ed
in
to
t
w
o
m
ain
p
ar
ts
:
C
T
T
,
an
d
E
3
T
tab
les.
a.
T
h
e
C
T
T
tab
les
th
at
s
to
r
e
m
et
ad
ata
(
i.e
.
d
ata
ab
o
u
t
d
atab
ase
s
tr
u
ctu
r
e)
ar
e
th
e
p
h
y
s
ical
tab
les
th
at
ex
is
ted
an
d
s
h
ar
ed
b
et
w
ee
n
all
te
n
a
n
t
s
.
T
h
ese
tab
les
ar
e
cr
ea
ted
b
y
ea
ch
te
n
an
t
ad
m
in
i
s
tr
ato
r
s
a
n
d
th
e
n
u
m
b
er
o
f
th
ese
tab
les
is
u
n
li
m
ited
.
T
h
e
q
u
er
y
th
a
t
is
b
ased
o
n
d
ata
d
ef
in
itio
n
la
n
g
u
a
g
e
(
DDL
)
d
ea
ls
w
ith
th
e
C
T
T
tab
les.
b.
T
h
e
E
3
T
tab
les
th
at
s
to
r
e
t
h
e
t
en
an
t
's
d
ata.
T
h
ese
tab
les
ar
e
r
esp
o
n
s
ib
le
f
o
r
th
e
cr
ea
tio
n
o
f
th
e
VE
T
tab
les
to
estab
lis
h
t
h
e
v
ir
t
u
al
d
ata
s
tr
u
ctu
r
e
t
h
at
ea
ch
te
n
an
t
h
as,
wh
ich
ca
n
b
e
cr
ea
ted
to
b
e
co
n
v
en
ie
n
t
f
o
r
ea
ch
ten
an
t
r
eq
u
ir
e
m
en
ts
a
s
s
h
o
w
n
in
Fi
g
u
r
e
2
.
T
h
ese
tab
les
ar
e
ad
d
ed
to
th
e
p
r
ev
io
u
s
l
y
E
E
T
tab
les
to
en
s
u
r
e
th
at
t
h
is
s
c
h
e
m
a
is
c
o
m
p
atib
le
w
it
h
an
y
te
n
an
t
n
ee
d
s
.
T
h
e
q
u
er
y
th
at
i
s
b
ased
o
n
d
ata
m
an
ip
u
latio
n
lan
g
u
a
g
e
(
DM
L
)
d
ea
ls
w
ith
t
h
e
E
3
T
ta
b
les.
Fig
u
r
e
2
.
E
n
h
a
n
ce
d
e
last
ic
e
x
t
en
s
io
n
t
ab
les
T
h
e
E
3
T
tab
les
p
r
o
v
id
e
h
ig
h
s
ca
lab
ilit
y
,
lo
w
s
p
ac
e
o
v
er
h
ea
d
,
an
d
f
lex
ib
il
it
y
f
o
r
t
h
e
f
o
llo
w
i
n
g
r
ea
s
o
n
s
:
T
h
e
to
tal
n
u
m
b
er
o
f
tab
les
f
r
o
m
m
u
ltip
le
t
en
an
t
s
is
a
f
i
x
ed
n
u
m
b
er
an
d
n
o
t
to
o
lar
g
e.
T
h
en
th
e
n
u
m
b
er
o
f
tab
le
s
d
o
es
n
o
t
g
r
o
w
li
n
ea
r
l
y
w
it
h
t
h
e
n
u
m
b
er
o
f
te
n
an
ts
.
E
li
m
i
n
a
te
th
e
ex
i
s
te
n
ce
o
f
NUL
L
v
al
u
es c
o
m
p
ar
i
n
g
o
t
h
e
r
m
u
lt
iten
a
n
c
y
tech
n
iq
u
es s
u
c
h
as
u
n
i
v
er
s
al
tab
le
tec
h
n
iq
u
e
as d
is
cu
s
s
ed
b
ef
o
r
e.
L
o
w
s
to
r
ag
e
n
ee
d
ed
as
all
t
h
e
ten
a
n
ts
ar
e
p
u
t
in
to
th
e
s
a
m
e
tab
les
co
n
s
id
er
in
g
i
m
p
o
r
tan
ce
.
I
t
is
m
o
r
e
f
lex
ib
le
b
ec
a
u
s
e
th
e
co
s
t o
f
ad
d
in
g
n
e
w
o
r
d
eletin
g
o
ld
attr
ib
u
tes is
m
u
c
h
s
m
al
ler
th
a
n
o
th
er
ap
p
r
o
ac
h
es.
3
.
2
.
T
he
NXD
-
E
3
T
Da
t
a
ba
s
e
I
n
th
is
s
ec
tio
n
,
t
h
e
NX
D
-
E
3
T
s
ch
e
m
a
i
s
p
r
o
p
o
s
ed
as
a
co
m
b
in
at
io
n
o
f
th
e
E
3
T
an
d
Nativ
e
XM
L
d
atab
ases
.
T
h
e
Nati
v
e
XM
L
d
atab
ase
is
u
s
ed
to
m
in
i
m
ize
th
e
a
m
o
u
n
t
o
f
d
ata
p
lace
d
i
n
t
h
e
m
e
m
o
r
y
a
n
d
i
m
p
r
o
v
e
t
h
e
p
er
f
o
r
m
an
ce
o
f
t
h
e
E
3
T
b
y
r
ed
u
ci
n
g
t
h
e
ac
ce
s
s
ti
m
e.
I
n
t
h
e
b
e
g
i
n
n
i
n
g
,
t
h
e
ap
p
licatio
n
p
r
o
g
r
a
m
in
ter
f
ac
e
(
A
P
I
)
g
ath
er
th
e
i
n
f
o
r
m
atio
n
d
ata
f
r
o
m
th
e
d
if
f
er
en
t
in
ter
f
ac
es
an
d
d
ev
ice
s
.
T
h
e
q
u
e
r
y
ac
ce
s
s
co
n
tr
o
l
ch
ec
k
s
th
e
p
r
iv
ile
g
e
o
f
t
h
e
te
n
a
n
t
'
s
q
u
er
y
to
ac
ce
s
s
ei
th
er
C
T
T
o
r
VE
T
.
T
h
en
th
e
NXD
tar
g
et
s
th
e
s
elec
ted
tab
les
to
lo
ad
it.
an
d
th
e
n
,
t
h
e
q
u
er
ies
ar
e
p
u
s
h
ed
to
th
e
Qu
er
y
o
p
ti
m
izer
w
h
ic
h
ca
r
r
ies
o
u
t
th
e
r
eq
u
ir
ed
f
u
n
ct
io
n
.
Fi
n
all
y
,
th
e
q
u
er
ies ar
e
p
ass
ed
to
b
e
ac
ce
s
s
d
ata
an
d
p
r
o
ce
s
s
ed
as sh
o
w
n
i
n
Fi
g
u
r
e
3
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
n
t J
E
lec
&
C
o
m
p
E
n
g
I
SS
N:
2
0
8
8
-
8708
A
n
a
tive
en
h
a
n
ce
d
ela
s
tic
ex
ten
s
io
n
ta
b
les mu
lti
-
ten
a
n
t
d
a
ta
b
a
s
e
(
Ma
g
y
E
l B
a
n
h
a
w
y)
6623
Fig
u
r
e
3
.
NXD
-
E
3
T
s
ch
e
m
a
W
h
en
NXD
d
ata
is
lo
ad
ed
in
to
r
elatio
n
al
d
atab
ases
,
NXD
r
ec
o
g
n
izes
an
d
u
n
d
er
s
ta
n
d
s
th
e
q
u
er
ie
s
n
ee
d
to
b
e
t
r
an
s
f
o
r
m
ed
in
to
SQL
q
u
er
ies
i
n
th
e
r
elatio
n
al
d
ata.
T
h
e
ad
v
an
tag
e
o
f
t
h
is
tec
h
n
iq
u
e
is
th
a
t
it
d
o
es
n
o
t
d
e
m
a
n
d
m
a
n
y
m
o
d
if
icat
i
o
n
s
o
f
t
h
e
ex
i
s
ti
n
g
d
ata
b
ase
en
g
i
n
e.
Me
r
g
in
g
t
h
e
E
3
T
d
ata
b
ase
w
it
h
t
h
e
NXD
w
il
l
p
r
o
v
id
e
t
h
e
m
u
lti
-
te
n
a
n
c
y
d
atab
ases
to
b
e
r
elatio
n
al
w
it
h
t
h
e
v
ir
t
u
al
tab
les
to
ea
ch
te
n
an
t
a
s
w
e
ll
a
s
w
i
ll
in
cr
ea
s
e
t
h
e
s
p
ee
d
an
d
d
ec
r
ea
s
e
th
e
r
esp
o
n
s
e
ex
ec
u
tio
n
ti
m
e
o
f
t
h
e
m
u
l
ti
-
ten
a
n
t
d
a
tab
ase.
C
o
n
s
id
er
i
n
g
th
e
NXD
i
s
a
m
id
d
le
la
y
er
b
et
w
ee
n
th
e
te
n
a
n
t
r
eq
u
est
s
an
d
t
h
e
q
u
er
y
r
es
u
lt,
an
d
t
h
e
ac
tu
a
l
tab
les
eith
er
C
T
T
o
r
VE
T
,
th
is
la
y
er
co
n
s
u
m
es
less
m
e
m
o
r
y
.
T
h
en
all
q
u
er
y
p
r
o
ce
s
s
in
g
is
p
as
s
ed
in
to
a
r
elatio
n
al
q
u
er
y
o
p
tim
izer
w
it
h
o
u
t
a
n
y
ex
tr
a
p
r
o
ce
s
s
in
g
w
o
r
k
.
U
s
in
g
N
XD
-
E
3
T
h
a
s
t
w
o
m
a
in
o
b
j
e
ctiv
es.
Firs
t,
q
u
er
y
th
e
d
atab
ase
u
s
in
g
a
co
m
m
o
n
q
u
er
y
lan
g
u
ag
e.
Seco
n
d
,
s
u
p
p
o
r
t m
u
ltip
le
te
n
an
ts
a
n
d
s
u
b
-
u
s
er
s
r
o
les.
4.
RE
SU
L
T
S
A
ND
D
I
SCU
SS
I
O
NS
I
n
t
h
is
s
ec
tio
n
,
th
e
p
er
f
o
r
m
a
n
ce
o
f
th
e
p
r
o
p
o
s
ed
NXD
-
E
3
T
s
ch
e
m
a
is
e
v
al
u
ated
.
T
h
e
p
r
o
p
o
s
ed
s
ch
e
m
a
is
co
m
p
ar
ed
ag
ain
s
t
E
E
T
an
d
E
3
T
o
n
a
h
eter
o
g
en
eo
u
s
I
o
T
d
atab
ase
[
2
8
]
.
M
o
r
eo
v
er
,
th
e
p
r
o
p
o
s
ed
s
ch
e
m
a
is
co
m
p
ar
ed
ag
a
in
s
t
v
ar
ian
t
m
u
lti
-
te
n
an
t
tech
n
iq
u
es;
P
r
iv
ate
tab
les,
E
x
te
n
s
io
n
tab
les,
U
n
iv
er
s
al
tab
les,
P
iv
o
t
tab
les,
C
h
u
n
k
t
ab
les,
C
h
u
n
k
f
o
ld
i
n
g
,
XM
L
tab
les,
E
E
T
,
an
d
E
3
T
,
w
h
er
e
th
is
ev
al
u
atio
n
is
i
m
p
le
m
en
ted
o
n
a
tr
ad
itio
n
all
y
s
tr
u
ct
u
r
ed
d
atab
ase
[
1
3
,
14]
.
T
h
e
p
r
o
p
o
s
ed
s
ch
e
m
a
s
i
m
u
la
tes
a
r
ea
l
m
u
lti
-
te
n
an
t
s
ce
n
ar
io
b
y
p
as
s
in
g
q
u
er
y
r
eq
u
e
s
ts
f
r
o
m
m
a
n
y
te
n
a
n
ts
co
n
c
u
r
r
en
tl
y
a
n
d
b
y
a
f
f
ec
ti
n
g
m
a
n
y
n
u
m
b
er
s
o
f
r
o
w
s
a
n
d
t
h
e
n
e
v
alu
a
te
t
h
e
s
o
lu
tio
n
s
b
y
a
n
al
y
zin
g
th
e
ex
ec
u
tio
n
ti
m
e
d
at
a
ca
p
tu
r
ed
d
u
r
in
g
ex
ec
u
t
in
g
t
h
o
s
e
e
x
p
er
i
m
e
n
t
s
.
T
h
e
ex
p
er
i
m
e
n
ts
w
er
e
co
m
p
le
ted
o
n
f
o
u
r
d
if
f
er
en
t q
u
er
y
t
y
p
es
w
h
ich
ar
e
s
elec
t,
in
s
er
t,
u
p
d
ate
,
an
d
d
elete
to
v
e
r
if
y
t
h
e
E
3
T
p
er
f
o
r
m
a
n
ce
.
4
.
1
.
E
x
peri
m
ent
a
l
da
t
a
s
et
T
h
e
ex
p
er
i
m
en
t
w
as
i
m
p
le
m
en
ted
w
it
h
A
p
ac
h
e
Ver
s
io
n
2
.
4
.
1
8
,
P
H
P
Ver
s
io
n
7
.
4
,
an
d
M
y
SQ
L
Ver
s
io
n
8
.
0
.
4.
T
h
is
p
ap
er
d
at
ab
ase
s
tr
u
ct
u
r
e
is
d
ep
lo
y
ed
i
n
a
s
er
v
er
p
latf
o
r
m
HP
P
r
o
L
ian
t
M
L
3
5
0
Gen
1
0
Ser
v
er
T
o
w
er
.
T
ab
le
3
s
h
o
w
s
t
h
e
s
p
ec
if
icatio
n
s
o
f
t
h
e
u
s
ed
p
latf
o
r
m
.
T
ab
le
3
.
Sp
ec
if
icatio
n
s
o
f
t
h
e
u
s
ed
p
latf
o
r
m
O
p
e
r
a
t
i
n
g
sy
st
e
m
W
i
n
d
o
w
s
S
e
r
v
e
r
2
0
1
9
P
r
o
c
e
sso
r
I
n
t
e
l
®
X
e
o
n
®
S
c
a
l
a
b
l
e
4
2
1
0
(
1
0
c
o
r
e
,
2
.
2
G
H
z
,
1
3
.
7
5
M
B
,
8
5
W
)
M
e
mo
r
y
3
2
G
B
R
D
I
M
M
D
R
S
t
o
r
a
g
e
c
a
p
a
c
i
t
y
p
e
r
d
i
s
k
4
x
8
T
B
4.
2
.
T
he
NXD
-
E
3
T
i
m
p
le
m
e
nta
t
io
n o
n uns
t
ruct
ured
I
o
T
da
t
a
ba
s
e
I
n
th
i
s
co
m
p
ar
is
o
n
,
t
h
e
p
r
o
p
o
s
ed
s
ch
e
m
a
i
s
co
m
p
ar
ed
ag
ai
n
s
t
E
E
T
an
d
E
3
T
o
n
a
h
eter
o
g
e
n
eo
u
s
I
o
T
d
atab
ase
in
ter
m
s
o
f
t
h
e
ex
ec
u
tio
n
ti
m
e.
T
h
e
r
esu
lts
o
f
t
h
is
ex
p
er
i
m
en
t
ar
e
ex
ec
u
ted
an
d
ca
lcu
lated
o
n
1
,
1
0
,
5
0
,
1
0
0
,
an
d
1
0
0
0
r
o
w
s
[
2
4
]
.
Fig
u
r
e
4
s
h
o
w
s
th
e
e
f
f
ec
t
o
f
i
n
cr
ea
s
i
n
g
t
h
e
n
u
m
b
er
o
f
r
ec
o
r
d
s
o
n
th
e
i
n
s
er
tio
n
o
p
er
atio
n
.
I
t
s
h
o
w
s
t
h
at
t
h
e
av
er
ag
e
e
x
ec
u
t
io
n
ti
m
e
o
f
th
e
NXD
-
E
3
T
is
ap
p
r
o
x
i
m
atel
y
4
5
%
f
a
s
ter
th
a
n
th
e
a
v
er
ag
e
e
x
ec
u
tio
n
ti
m
e
o
f
th
e
E
3
T
.
Fig
u
r
e
5
s
h
o
w
s
t
h
e
ef
f
ec
t
o
f
th
is
i
n
cr
ea
s
e
o
n
t
h
e
u
p
d
at
e
o
p
er
atio
n
.
T
h
e
r
esu
lt
s
h
o
w
s
t
h
at
th
e
a
v
er
ag
e
o
f
th
e
ex
ec
u
tio
n
ti
m
e
o
f
th
e
NXD
-
E
3
T
is
3
0
%
f
aster
th
an
th
e
a
v
er
ag
e
ex
ec
u
t
io
n
t
i
m
e
o
f
E
3
T
.
An
o
th
er
n
o
ticea
b
le
f
ea
t
u
r
e
t
h
at
t
h
is
p
er
f
o
r
m
a
n
ce
i
s
ta
k
i
n
g
a
lin
e
f
u
n
c
tio
n
w
it
h
th
e
in
cr
ea
s
e
o
f
t
h
e
r
o
w
s
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
SS
N
:
2
0
8
8
-
8708
I
n
t J
E
lec
&
C
o
m
p
E
n
g
,
Vo
l.
10
,
No
.
6
,
Dec
em
b
er
2
0
2
0
:
6
6
1
8
-
6
6
2
8
6624
Th
e
Dele
te
o
p
er
atio
n
is
s
h
o
w
n
i
n
F
ig
u
r
e
6
.
T
h
e
r
esu
lt
s
h
o
w
s
t
h
at
t
h
e
a
v
er
ag
e
o
f
t
h
e
e
x
e
cu
tio
n
ti
m
e
o
f
t
h
e
NXD
-
E
3
T
is
al
m
o
s
t
th
e
s
a
m
e
as
th
e
av
er
a
g
e
o
f
th
e
ex
ec
u
tio
n
ti
m
e
o
f
E
3
T
w
it
h
s
m
al
l
n
u
m
b
er
s
o
f
r
o
ws
o
r
ev
en
a
litt
le
f
as
ter
.
B
u
t
as
th
e
n
u
m
b
er
o
f
r
o
w
s
in
c
r
ea
s
e
s
th
e
ex
ec
u
tio
n
ti
m
e
o
f
NX
D
-
E
3
T
b
ec
o
m
es
f
aster
.
T
h
e
Selectio
n
o
p
er
atio
n
is
s
h
o
w
n
i
n
Fi
g
u
r
e
7
.
T
h
e
r
esu
lt
s
h
o
w
s
th
a
t
th
e
e
x
ec
u
tio
n
ti
m
e
o
f
t
h
e
o
f
NX
D
-
E
3
T
is
ap
p
r
o
x
im
a
tel
y
t
h
e
s
a
m
e
as
th
e
av
er
ag
e
o
f
th
e
ex
ec
u
tio
n
ti
m
e
E
3
T
ev
en
af
ter
th
e
n
u
m
b
er
o
f
r
ec
o
r
d
s
in
cr
ea
s
es
th
e
s
a
m
e
ti
m
e
is
ta
k
e
n
in
ea
c
h
m
et
h
o
d
.
I
NSERT
UP
DA
T
E
Fig
u
r
e
4
.
T
h
e
ex
ec
u
tio
n
ti
m
e
o
f
I
NSERT
q
u
er
y
Fig
u
r
e
5
.
T
h
e
ex
ec
u
tio
n
ti
m
e
o
f
UP
DA
T
E
q
u
er
y
DE
L
E
T
E
SEL
E
C
T
Fig
u
r
e
6
.
T
h
e
ex
ec
u
tio
n
ti
m
e
o
f
DE
L
E
T
E
q
u
er
y
Fig
u
r
e
7
.
T
h
e
ex
ec
u
tio
n
ti
m
e
o
f
SEL
E
C
T
q
u
er
y
4
.
3
.
T
he
NXD
-
E
3
T
i
m
p
le
m
e
nta
t
io
n o
n str
uct
ured
da
t
a
ba
s
e
I
n
th
is
s
u
b
-
s
ec
tio
n
th
e
co
m
p
ar
is
o
n
is
im
p
lem
en
ted
o
n
a
tr
a
d
itio
n
ally
s
tr
u
ctu
r
ed
d
atab
ase,
th
e
p
r
o
p
o
s
ed
s
ch
em
a
is
co
m
p
ar
ed
ag
ain
s
t
d
if
f
er
en
t
m
u
lti
-
ten
an
t
tech
n
iq
u
es
s
u
ch
as
P
r
iv
ate
T
ab
les,
E
x
ten
s
io
n
T
ab
les,
Un
iv
er
s
al
T
ab
le,
P
iv
o
tT
ab
les,
C
h
u
n
k
T
ab
le,
C
h
u
n
k
Fo
ld
in
g
,
XM
L
,
an
d
E
E
T
.
T
h
e
r
esu
lts
o
f
th
is
ex
p
er
im
en
t
ar
e
ex
ec
u
ted
an
d
ca
lcu
lated
w
h
en
o
p
er
atin
g
1
,
5
0
,
o
r
1
0
0
r
o
w
s
.
I
n
s
er
tin
g
Qu
er
y
E
x
p
er
im
en
tal
R
esu
lt.
T
h
is
ex
p
er
im
en
t
is
s
h
o
w
in
g
th
at
th
e
av
er
ag
e
ex
ec
u
tio
n
tim
e
o
f
th
e
NXD
-
E
3
T
is
ap
p
r
o
x
im
ately
2
9
%
f
aster
th
an
th
e
av
er
ag
e
ex
ec
u
tio
n
tim
e
o
f
th
e
E
E
T
Sch
em
a
as
p
r
esen
ted
in
Fig
u
r
e
8
.
NXD
-
E
3
T
Sch
em
a
is
co
n
s
id
er
ed
th
e
f
astes
t
av
er
ag
e
ex
ec
u
tio
n
tim
e
f
r
o
m
all
m
u
lti
-
ten
an
t
tech
n
iq
u
es
in
th
e
in
s
er
t
q
u
er
y
.
Up
d
atin
g
q
u
er
y
ex
p
er
im
en
tal
r
esu
lt.
T
h
is
ex
p
er
im
en
t
is
s
h
o
w
in
g
th
at
th
e
av
er
ag
e
ex
ec
u
tio
n
tim
e
o
f
th
e
NXD
-
E
3
T
9
%
f
aster
th
an
th
e
av
er
ag
e
ex
ec
u
tio
n
tim
e
o
f
th
e
E
E
T
Sch
em
a
in
Fig
u
r
e
9
.
NXD
-
E
3
T
Sch
em
a
is
co
n
s
id
er
ed
th
e
f
astes
t
av
er
ag
e
ex
ec
u
tio
n
tim
e
f
r
o
m
all
m
u
lti
-
ten
an
t
tech
n
iq
u
es
in
th
e
u
p
d
ate
q
u
er
y
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
n
t J
E
lec
&
C
o
m
p
E
n
g
I
SS
N:
2
0
8
8
-
8708
A
n
a
tive
en
h
a
n
ce
d
ela
s
tic
ex
ten
s
io
n
ta
b
les mu
lti
-
ten
a
n
t
d
a
ta
b
a
s
e
(
Ma
g
y
E
l B
a
n
h
a
w
y)
6625
Dele
tin
g
q
u
er
y
ex
p
er
im
en
tal
r
esu
lt
.
T
h
is
ex
p
er
im
en
t
is
s
h
o
w
in
g
th
at
th
e
av
er
ag
e
ex
ec
u
tio
n
tim
e
o
f
th
e
NXD
-
E
3
T
,
is
ap
p
r
o
x
im
ately
2
4
%
f
aster
th
an
th
e
av
er
ag
e
ex
ec
u
tio
n
tim
e
o
f
th
e
E
E
T
as
p
r
esen
ted
in
Fig
u
r
e
1
0
.
T
h
e
d
elete
an
d
th
e
in
s
er
t
q
u
er
y
ap
p
r
o
x
im
ately
h
av
e
th
e
s
am
e
av
er
ag
e
as
b
o
th
h
av
in
g
alm
o
s
t
th
e
s
am
e
p
r
o
ce
s
s
in
g
m
eth
o
d
s
.
T
h
e
n
u
m
b
er
ex
ec
u
tin
g
th
e
q
u
er
y
is
in
ascen
d
in
g
r
elatio
n
s
h
i
p
w
ith
th
e
n
u
m
b
er
o
f
r
o
w
s
af
f
ec
ted
.
Selectin
g
Qu
er
y
E
x
p
er
im
en
tal
R
esu
lt.
T
h
is
ex
p
er
im
en
t
is
s
h
o
w
in
g
th
at
th
e
av
er
ag
e
ex
ec
u
tio
n
tim
e
o
f
th
e
NXD
-
E
3
T
is
n
ea
r
ly
8
%
f
aster
th
an
th
e
av
er
ag
e
ex
ec
u
tio
n
tim
e
o
f
th
e
E
E
T
as
in
Fig
u
r
e
1
1
.
T
h
e
SEL
E
C
T
q
u
er
y
is
th
e
m
o
r
e
co
m
p
licated
q
u
er
y
in
an
y
m
u
lti
-
ten
an
t
tech
n
iq
u
e
as
it
r
eq
u
ir
es
m
o
r
e
p
r
o
ce
s
s
in
g
in
J
OI
N
o
p
er
atio
n
an
d
m
o
r
e
u
n
d
er
s
tan
d
in
g
o
f
th
e
tech
n
iq
u
e.
T
h
e
tim
e
o
f
th
e
q
u
er
y
ex
ec
u
tin
g
is
in
a
lin
ea
r
r
elatio
n
s
h
ip
w
ith
th
e
n
u
m
b
er
o
f
r
o
w
s
af
f
ec
ted
.
W
ith
all
th
ese
ch
al
len
g
es
th
e
NXD
-
E
3
T
Sch
em
a
h
as
m
an
ag
ed
to
p
er
f
o
r
m
th
is
q
u
er
y
w
ith
m
in
im
u
m
r
esp
o
n
s
e
ex
ec
u
tio
n
tim
e
in
co
m
p
ar
is
o
n
to
th
e
m
u
lti
-
ten
an
t
tech
n
iq
u
es.
I
NSERT
Fig
u
r
e
8
.
T
h
e
ex
ec
u
tio
n
ti
m
e
o
f
I
NSERT
q
u
er
y
UP
DA
T
E
Fig
u
r
e
9
.
T
h
e
ex
ec
u
tio
n
ti
m
e
o
f
UP
DA
T
E
q
u
er
y
Evaluation Warning : The document was created with Spire.PDF for Python.
I
SS
N
:
2
0
8
8
-
8708
I
n
t J
E
lec
&
C
o
m
p
E
n
g
,
Vo
l.
10
,
No
.
6
,
Dec
em
b
er
2
0
2
0
:
6
6
1
8
-
6
6
2
8
6626
DE
L
E
T
E
Fig
u
r
e
1
0
.
T
h
e
ex
ec
u
tio
n
ti
m
e
o
f
DE
L
E
T
E
q
u
er
y
SEL
E
C
T
Fig
u
r
e
1
1
.
T
h
e
ex
ec
u
tio
n
ti
m
e
o
f
SEL
E
C
T
q
u
er
y
5.
CO
NCLU
SI
O
N
I
n
th
is
p
ap
er
,
a
n
ati
v
e
e
n
h
a
n
ce
d
elastic
e
x
te
n
s
io
n
tab
les
(
NXD
-
E
3
T
)
d
atab
ase
is
in
tr
o
d
u
ce
d
as
a
m
u
lti
-
ten
a
n
c
y
d
atab
ase
s
y
s
t
e
m
.
T
h
e
NXD
-
E
3
T
Sch
e
m
a
p
er
m
its
te
n
a
n
ts
to
cr
ea
te
d
atab
ases
w
it
h
d
if
f
er
en
t
r
eq
u
ir
e
m
en
ts
n
ee
d
ed
f
o
r
an
y
b
u
s
i
n
ess
w
h
ic
h
ac
h
ie
v
e
h
i
g
h
s
ca
lab
ilit
y
a
n
d
all
n
ee
d
ed
p
r
o
g
r
a
m
m
i
n
g
f
ea
t
u
r
es
w
it
h
a
h
i
g
h
av
er
ag
e
r
esp
o
n
s
e
ti
m
e.
T
h
e
NXD
-
E
3
T
Sch
e
m
a
en
ab
les
ten
a
n
ts
to
o
w
n
th
ei
r
elastic
r
elatio
n
al
d
atab
ase
s
ch
e
m
a.
I
t
ca
n
b
e
im
p
le
m
e
n
ted
i
n
th
e
I
o
T
s
y
s
te
m
s
e
f
f
icien
tl
y
.
F
u
t
u
r
e
p
u
b
lica
tio
n
s
w
ill
f
o
cu
s
o
n
m
er
g
i
n
g
th
e
No
SQ
L
to
th
e
E
3
T
as
th
e
No
SQL
d
ata
s
t
o
r
ag
e
ai
m
s
to
h
a
n
d
le
d
ata
in
th
e
I
o
T
s
y
s
te
m
s
m
o
r
e
ac
c
u
r
atel
y
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
n
t J
E
lec
&
C
o
m
p
E
n
g
I
SS
N:
2
0
8
8
-
8708
A
n
a
tive
en
h
a
n
ce
d
ela
s
tic
ex
ten
s
io
n
ta
b
les mu
lti
-
ten
a
n
t
d
a
ta
b
a
s
e
(
Ma
g
y
E
l B
a
n
h
a
w
y)
6627
RE
F
E
R
E
NC
E
S
[1
]
A
.
Ju
m
a
g
a
li
y
e
v
,
“
A
M
o
d
e
li
n
g
L
a
n
g
u
a
g
e
f
o
r
M
u
lt
i
-
ten
a
n
t
Da
ta
A
r
c
h
it
e
c
tu
re
Ev
o
lu
ti
o
n
in
Clo
u
d
A
p
p
li
c
a
ti
o
n
s,”
P
h
D T
h
e
sis
,
L
a
n
c
a
ste
r
Un
iv
e
rsit
y
,
2
0
1
9
.
[2
]
J.
K.
R.
S
a
str
y
a
n
d
M
.
T
.
Ba
s
u
,
“
S
e
c
u
rin
g
m
u
lt
i
-
ten
a
n
c
y
s
y
ste
m
s
th
ro
u
g
h
m
u
lt
i
DB
in
sta
n
c
e
s
a
n
d
m
u
lt
ip
le
d
a
tab
a
se
s
o
n
d
if
f
e
r
e
n
t
p
h
y
sic
a
l
s
e
rv
e
rs,”
In
t
e
rn
a
ti
o
n
a
l
J
o
u
rn
a
l
o
f
El
e
c
tr
ica
l
and
C
o
mp
u
t
er
En
g
i
n
e
e
rin
g
(
IJ
ECE
)
,
v
o
l.
9
,
n
o
.
2
,
p
p
.
1
3
8
5
-
1
3
9
2
,
2
0
1
9
.
[3
]
L
.
L
i,
e
t
a
l.
,
“
M
u
lt
i
-
ten
a
n
t
d
a
ta
a
u
th
e
n
ti
c
a
ti
o
n
m
o
d
e
l
f
o
r
S
a
a
S
,
”
Op
e
n
Cy
b
e
rn
e
ti
c
s
a
n
d
S
y
st
e
mic
s
J
o
u
rn
a
l
,
v
o
l.
8
,
n
o
.
1
,
p
p
.
3
2
2
-
3
2
9
,
2
0
1
4
.
[4
]
A
.
Ri
c
o
,
e
t
a
l.
,
“
Ex
t
e
n
d
in
g
m
u
lt
i
-
ten
a
n
t
a
rc
h
it
e
c
tu
re
s:
a
d
a
tab
a
se
m
o
d
e
l
f
o
r
a
m
u
lt
i
-
targ
e
t
s
u
p
p
o
rt
in
S
a
a
S
a
p
p
li
c
a
ti
o
n
s,”
En
ter
p
rise
In
f
o
rm
a
ti
o
n
S
y
st
e
ms
,
v
o
l.
1
0
,
n
o
.
4
,
p
p
.
4
0
0
-
4
2
1
,
2
0
1
6
.
[5
]
G
.
B.
P
a
ll
a
v
i
a
n
d
P
.
Ja
y
a
r
e
k
h
a
,
“
A
n
e
ff
i
c
ien
t
re
so
u
rc
e
sh
a
rin
g
tec
h
n
i
q
u
e
f
o
r
m
u
lt
i
-
ten
a
n
t
d
a
tab
a
se
s,”
In
t
e
rn
a
ti
o
n
a
l
J
o
u
rn
a
l
o
f
El
e
c
tr
ica
l
a
n
d
C
o
mp
u
t
er
En
g
i
n
e
e
rin
g
(
IJ
ECE
)
,
v
o
l.
1
0
,
n
o
.
3
,
p
p
.
3
2
1
6
-
3
2
2
6
,
2
0
2
0
.
[6
]
T
.
A
.
M
.
P
h
a
n
,
e
t
a
l.
,
“
Clo
u
d
d
a
tab
a
se
s
f
o
r
in
tern
e
t
-
of
-
th
in
g
s
d
a
ta,”
2
0
1
4
IEE
E
In
t
e
rn
a
ti
o
n
a
l
Co
n
f
e
re
n
c
e
o
n
In
ter
n
e
t
o
f
T
h
i
n
g
s,
(
iT
h
i
n
g
s
2
0
1
4
)
,
2
0
1
4
IEE
E
Gr
e
e
n
Co
mp
u
t
i
n
g
a
n
d
Co
mm
u
n
ica
ti
o
n
s
(
Gr
e
e
n
C
o
m
2
0
1
4
),
a
n
d
IEE
E
Cy
b
e
r
,
P
h
y
sic
a
l
a
n
d
S
o
c
ia
l
Co
mp
u
t
in
g
,
p
p
.
1
1
7
-
1
2
4
,
2
0
1
4
.
[7
]
K.
K.
P
a
tel,
e
t
a
l.
,
“
In
tern
e
t
o
f
T
h
in
g
s
-
IO
T
:
D
e
f
in
it
io
n
,
Ch
a
ra
c
ter
isti
c
s,
A
rc
h
it
e
c
tu
re
,
En
a
b
li
n
g
Tec
h
n
o
lo
g
ies
,
A
p
p
li
c
a
ti
o
n
&
a
m
p
;
F
u
tu
re
Ch
a
ll
e
n
g
e
s,”
In
t
e
rn
a
ti
o
n
a
l
J
o
u
rn
a
l
o
f
En
g
in
e
e
rin
g
S
c
i
e
n
c
e
a
n
d
Co
mp
u
t
i
n
g
,
v
o
l
.
6
,
n
o
.
5
,
p
p
.
6
1
2
2
-
6
1
3
1
,
2
0
1
6
.
[8
]
J.
A
.
S
tan
k
o
v
ic,
“
Re
se
a
r
c
h
d
irec
ti
o
n
s
f
o
r
t
h
e
in
tern
e
t
o
f
th
i
n
g
s,”
IEE
E
In
ter
n
e
t
o
f
T
h
i
n
g
s
J
o
u
rn
a
l
,
v
o
l.
1
,
n
o
.
1
,
p
p
.
3
-
9
,
2
0
1
4
.
[9
]
S
.
Ch
e
rrier,
e
t
a
l.
,
“
M
u
l
ti
-
ten
a
n
c
y
in
d
e
c
e
n
tralise
d
Io
T
,
”
IEE
E
W
o
r
ld
F
o
ru
m
o
n
In
ter
n
e
t
of
T
h
i
n
g
s
,
(
WF
-
Io
T
2
0
1
5
)
,
p
p
.
2
5
6
-
2
6
1
,
2
0
1
5
.
[1
0
]
C.
L
i,
e
t
a
l.
,
“
D
y
n
a
m
i
c
m
u
lt
i
-
o
b
j
e
c
ti
v
e
o
p
ti
m
iz
e
d
re
p
li
c
a
p
lac
e
m
e
n
t
a
n
d
m
ig
ra
ti
o
n
stra
teg
ies
f
o
r
S
a
a
S
a
p
p
li
c
a
ti
o
n
s
in
e
d
g
e
c
lo
u
d
,
”
F
u
tu
r
e
Ge
n
e
r
a
t
io
n
Co
m
p
u
t
er
S
y
st
e
ms
,
v
o
l.
1
0
0
,
p
p
.
9
2
1
-
9
3
7
,
2
0
1
9
.
[1
1
]
E.
A
.
Bo
y
tso
v
,
“
De
sig
n
in
g
a
n
d
d
e
v
e
lo
p
m
e
n
t
o
f
a
n
i
m
it
a
ti
o
n
m
o
d
e
l
o
f
a
m
u
lt
it
e
n
a
n
t
d
a
tab
a
se
c
lu
ste
r,
”
Au
to
m
a
ti
c
Co
n
tro
l
a
n
d
Co
mp
u
t
er
S
c
i
e
n
c
e
s
,
v
o
l.
4
8
,
n
o
.
7
,
p
p
.
4
3
7
-
4
4
4
,
2
0
1
4
.
[1
2
]
S
.
K.
P
i
p
p
a
l
a
n
d
D.
S
.
Ku
sh
w
a
h
a
,
“
A
si
m
p
le,
a
d
a
p
tab
le
a
n
d
e
ff
icie
n
t
h
e
tero
g
e
n
e
o
u
s
m
u
lt
i
-
ten
a
n
t
d
a
tab
a
se
a
rc
h
it
e
c
tu
re
f
o
r
a
d
h
o
c
c
lo
u
d
,
”
J
o
u
rn
a
l
o
f
Clo
u
d
C
o
mp
u
t
i
n
g
:
Ad
v
a
n
c
e
s,
S
y
st
e
ms
a
n
d
Ap
p
l
ica
ti
o
n
,
p
p
.
1
-
1
4
,
2
0
1
3
.
[1
3
]
H.
Ya
ish
,
e
t
a
l.
,
“
A
P
ro
x
y
S
e
rv
ic
e
f
o
r
M
u
lt
i
-
ten
a
n
t
El
a
stic
Ex
ten
sio
n
T
a
b
les
,
”
T
ra
n
sa
c
ti
o
n
s
o
n
L
a
rg
e
-
S
c
a
le
Da
ta
a
md
K
n
o
wled
g
e
Ce
n
ter
e
d
S
y
ste
ms
XX
,
p
p
.
1
-
3
3
,
2
0
1
5
.
[1
4
]
H.
Ya
ish
,
e
t
a
l.
,
“
Ev
a
lu
a
ti
n
g
th
e
p
e
rf
o
r
m
a
n
c
e
o
f
m
u
lt
i
-
ten
a
n
t
El
a
stic
Ex
ten
sio
n
T
a
b
les
,
”
Pro
c
e
d
ia
Co
mp
u
t
er
S
c
i
e
n
c
e
,
v
o
l.
2
9
,
p
p
.
6
1
4
-
6
2
6
,
2
0
1
4
.
[1
5
]
A
.
I.
S
a
leh
,
e
t
a
l.
,
“
A
H
y
b
rid
M
u
lt
i
-
T
e
n
a
n
t
Da
tab
a
se
S
c
h
e
m
a
f
o
r
M
u
lt
i
-
L
e
v
e
l
Qu
a
li
ty
o
f
S
e
rv
ice
,
”
In
t
e
rn
a
ti
o
n
a
l
J
o
u
rn
a
l
o
f
A
d
v
an
ced
C
o
mp
u
t
er
S
c
i
e
n
c
e
a
n
d
Ap
p
l
ica
t
io
n
s
,
v
o
l.
5
,
n
o
.
1
1
,
p
p
.
1
3
2
-
1
3
9
,
2
0
1
4
.
[1
6
]
J.
Ka
b
b
e
d
ij
k
,
e
t
a
l.
,
“
M
u
lt
i
-
ten
a
n
t
A
rc
h
it
e
c
tu
re
Co
m
p
a
riso
n
,
”
E
u
ro
p
e
a
n
C
o
n
fer
e
n
c
e
o
n
S
o
f
twa
r
e
Arc
h
it
e
c
tu
re
,
p
p
.
2
0
2
-
2
0
9
,
2
0
1
4
.
[1
7
]
R.
P
.
M
a
h
a
p
a
tra
a
n
d
S
.
Kh
a
n
,
“
A
S
u
rv
e
y
O
f
S
q
l
In
jec
ti
o
n
Co
u
n
t
e
r
m
e
a
su
re
s,”
In
t
e
rn
a
ti
o
n
a
l
J
o
u
rn
a
l
o
f
Co
m
p
u
t
er
S
c
i
e
n
c
e
a
n
d
E
n
g
i
n
e
e
rin
g
S
u
rv
ey
,
v
o
l.
3
,
n
o
.
3
,
p
p
.
5
5
-
7
4
,
2
0
1
4
.
[1
8
]
A
.
Qta
ish
a
n
d
K.
A
h
m
a
d
,
“
X
A
n
c
e
sto
r:
A
n
e
ff
icie
n
t
m
a
p
p
in
g
a
p
p
ro
a
c
h
f
o
r
sto
rin
g
a
n
d
q
u
e
ry
in
g
X
M
L
d
o
c
u
m
e
n
ts
in
re
l
a
ti
o
n
a
l
d
a
tab
a
se
u
sin
g
p
a
t
h
-
b
a
s
e
d
tec
h
n
i
q
u
e
,
”
K
n
o
wled
g
e
-
Ba
se
d
S
y
st
e
ms
,
v
o
l.
1
1
4
,
p
p
.
1
6
7
-
1
9
2
,
2
0
1
6
.
[1
9
]
Y.
Ca
o
,
e
t
a
l.
,
“
S
u
p
p
o
rt
m
e
c
h
a
n
ism
s
f
o
r
c
lo
u
d
c
o
n
f
ig
u
ra
ti
o
n
u
si
n
g
X
M
L
f
il
terin
g
tec
h
n
iq
u
e
s:
A
c
a
se
stu
d
y
in
S
a
a
S
,
”
Fu
t
u
r
e
Ge
n
e
r
a
ti
o
n
Co
m
p
u
t
er
S
y
st
e
ms
,
v
o
l.
9
5
,
p
p
.
5
2
-
6
7
,
2
0
1
9
.
[2
0
]
O.
Os
e
m
w
e
g
ie,
e
t
a
l.
,
“
P
e
rf
o
rm
a
n
c
e
b
e
n
c
h
m
a
rk
in
g
o
f
k
e
y
-
v
a
lu
e
s
to
re
No
S
QL
d
a
tab
a
se
s,”
In
t
e
rn
a
ti
o
n
a
l
J
o
u
rn
a
l
o
f
El
e
c
tr
ica
l
a
n
d
C
o
mp
u
t
er
En
g
in
e
e
rin
g
,
v
o
l.
8
,
n
o
.
6
,
p
p
.
5
3
3
3
-
5
3
4
1
,
2
0
1
8
.
[2
1
]
I.
F
o
sic
a
n
d
K.
Š
o
li
c
,
“
G
ra
p
h
d
a
tab
a
se
a
p
p
ro
a
c
h
f
o
r
d
a
ta
sto
ri
n
g
,
p
re
se
n
tatio
n
a
n
d
m
a
n
ip
u
lati
o
n
,
”
2
0
1
9
4
2
n
d
In
t
e
rn
a
t
io
n
a
l
C
o
n
v
e
n
ti
o
n
o
n
In
f
o
r
ma
ti
o
n
a
n
d
C
o
mm
u
n
ica
ti
o
n
T
e
c
h
n
o
l
o
g
y
,
E
lec
tro
n
ics
a
n
d
M
icr
o
e
lec
tro
n
.
(
M
IPR
O
2
0
1
9
)
,
p
p
.
1
5
4
8
-
1
5
5
2
,
2
0
1
9
.
[2
2
]
S
.
Ba
lam
u
ru
g
a
n
a
n
d
A
.
Ay
y
a
s
a
m
y
,
“
P
e
rf
o
r
m
a
n
c
e
E
v
a
lu
a
ti
o
n
o
f
Na
ti
v
e
X
M
L
D
a
tab
a
se
a
n
d
X
M
L
En
a
b
le
d
Da
tab
a
se
,
”
In
t
e
rn
a
ti
o
n
a
l
J
o
u
r
n
a
l
o
f
Ad
v
a
n
c
e
d
Res
e
a
rc
h
in
Co
m
p
u
t
er
S
c
i
e
n
c
e
a
n
d
S
o
ft
w
a
re
En
g
in
e
e
rin
g
,
v
o
l.
7
,
n
o
.
5
,
p
p
.
1
8
2
-
1
9
1
,
2
0
1
7
.
[2
3
]
M
.
G
.
Kib
ria,
e
t
a
l.
,
“
A
f
r
a
m
e
w
o
rk
to
su
p
p
o
rt
d
a
ta
in
ter
o
p
e
ra
b
il
it
y
in
we
b
o
b
jec
ts
b
a
se
d
Io
T
e
n
v
iro
n
m
e
n
ts,
”
In
t
e
rn
a
t
io
n
a
l
C
o
n
f
e
re
n
c
e
o
n
I
n
f
o
r
ma
ti
o
n
a
n
d
Co
mm
u
n
ica
ti
o
n
T
e
c
h
n
o
l
ogy
C
o
n
v
e
rg
e
n
c
e
(
ICT
C)
,
p
p
.
2
9
-
3
1
,
2
0
1
7
.
[2
4
]
S
.
W
u
,
“
A
M
e
th
o
d
f
o
r
Bu
il
d
in
g
S
h
a
re
d
M
a
ss
iv
e
He
t
e
ro
g
e
n
e
o
u
s
Io
T
Da
ta
En
v
iro
n
m
e
n
t,
”
2
0
1
8
5
t
h
In
t
e
rn
a
t
io
n
a
l
Co
n
f
e
re
n
c
e
o
n
In
f
o
rm
a
ti
o
n
S
c
i
e
n
c
e
a
n
d
C
o
n
tro
l
E
n
g
in
e
e
rin
g
(
ICIS
CE
2
0
1
8
)
,
p
p
.
4
0
-
4
5
,
2
0
1
8
.
[2
5
]
M
.
W
in
c
k
ler
a
n
d
K.
Ku
u
sin
e
n
,
“
A
b
so
lu
te
In
d
irec
t
T
o
u
c
h
In
tera
c
ti
o
n
:
Im
p
a
c
t
o
f
Ha
p
ti
c
M
a
rk
s
a
n
d
A
n
im
a
t
e
d
V
isu
a
l,
”
In
t
.
Fed
.
In
f
.
Pro
c
e
ss
.
2
0
1
9
Pu
b
l.
b
y
S
p
rin
g
e
r
Na
t.
S
w
it
z.
AG
2
0
1
9
C.
Bo
g
d
a
n
a
l.
HC
S
E
2
0
1
8
,
L
NCS
1
1
2
6
2
,
v
o
l.
1
,
p
p
.
2
3
1
-
2
4
7
,
2
0
1
9
.
[2
6
]
N.
Da
lče
k
o
v
ić,
e
t
a
l.
,
“
En
a
b
li
n
g
th
e
Io
T
p
a
ra
d
ig
m
th
ro
u
g
h
m
u
lt
i
-
ten
a
n
c
y
su
p
p
o
rted
b
y
sc
a
lab
le
d
a
ta
a
c
q
u
isit
io
n
la
y
e
r,
”
An
n
a
ls
o
f
T
e
lec
o
mm
u
n
ica
t
io
n
,
v
o
l.
7
2
,
n
o
.
1
-
2
,
p
p
.
7
1
-
7
8
,
2
0
1
7
.
[2
7
]
M
.
U.
Ka
la
y
,
“
Da
tab
a
se
S
y
ste
m
S
u
g
g
e
stio
n
s
f
o
r
th
e
In
ter
n
e
t
o
f
T
h
in
g
s
(Io
T
)
S
y
ste
m
s,”
M
u
g
la
J
o
u
rn
a
l
o
f
S
c
i
e
n
c
e
and
T
e
c
h
n
o
l
ogy
,
p
p
.
4
6
-
5
2
,
2
0
1
8
.
[2
8
]
M
.
S
a
m
a
n
ieg
o
a
n
d
R.
De
ters
,
“
S
u
p
p
o
rti
n
g
Io
T
M
u
lt
i
-
T
e
n
a
n
c
y
o
n
E
d
g
e
De
v
ice
s,”
2
0
1
6
IEE
E
In
t
e
rn
a
ti
o
n
a
l
Co
n
f
e
re
n
c
e
o
n
In
ter
n
e
t
of
T
h
in
g
s
and
IEE
E
Gr
e
e
n
Co
mp
u
t
i
n
g
a
n
d
Co
mm
u
n
ica
ti
o
n
s
a
n
d
IEE
E
Cy
b
e
r,
Ph
y
s
ica
l
a
n
d
Soc
ia
l
Co
m
p
u
t
i
n
g
a
n
d
I
EE
E
S
ma
rt Da
ta
,
p
p
.
6
6
-
7
3
,
2
0
1
7
.
Evaluation Warning : The document was created with Spire.PDF for Python.