Let the following relational tables be given: R = (A, B, C) and S = (D, E, F) where A, B, C, D, E, and F are the attributes (columns). Write the SQL statements that will express each of the queries given below:
樣板 B 樹(shù) ( B - tree )
規(guī)則 :
(1) 每個(gè)節(jié)點(diǎn)內(nèi)元素個(gè)數(shù)在 [MIN,2*MIN] 之間, 但根節(jié)點(diǎn)元素個(gè)數(shù)為 [1,2*MIN]
(2) 節(jié)點(diǎn)內(nèi)元素由小排到大, 元素不重複
(3) 每個(gè)節(jié)點(diǎn)內(nèi)的指標(biāo)個(gè)數(shù)為元素個(gè)數(shù)加一
(4) 第 i 個(gè)指標(biāo)所指向的子節(jié)點(diǎn)內(nèi)的所有元素值皆小於父節(jié)點(diǎn)的第 i 個(gè)元素
(5) B 樹(shù)內(nèi)的所有末端節(jié)點(diǎn)深度一樣
The XML Toolbox converts MATLAB data types (such as double, char, struct, complex, sparse, logical) of any level of nesting to XML format and vice versa.
For example,
>> project.name = MyProject
>> project.id = 1234
>> project.param.a = 3.1415
>> project.param.b = 42
becomes with str=xml_format(project, off )
"<project>
<name>MyProject</name>
<id>1234</id>
<param>
<a>3.1415</a>
<b>42</b>
</param>
</project>"
On the other hand, if an XML string XStr is given, this can be converted easily to a MATLAB data type or structure V with the command V=xml_parse(XStr).
