Posts filed under ‘IT/Soft’
[vb] Merge several excel files into 1 separate worksheet
Thank you experts ~.~
[vbs] Get folder names / file names in a directory
‘Option explicit
Set fs = CreateObject(“Scripting.FileSystemObject”)
‘create output file
Set outFile = fs.CreateTextFile(“d:\folder_name.txt”)
‘set directory
Set oFolder = fs.GetFolder(“d:\”)
‘if get file name use this
‘Set oFiles = oFolder.Files
‘if get folder name use this
Set oSubFolder = oFolder.SubFolders
‘go through list
For Each i In oSubFolder
‘write to output
outFile.writeline i.Name
Next
WScript.Echo “Finish!”
3 Normal Forms in Relational Database Theory
I find this guide easiest to understand:
First normal form (no items appear more than once)
- each col must have a unique name
- order of rows and cols doesn’t matter
- each col must have a single data type
- no 2 rows can contain identical values
- each col must contain a single value
- cols cannot contain repeating groups
Second normal form (primary key determine value of other columns)
- in 1NF
- all non-key fields depend on all of the key fields
Third normal form (value not determined by any non-primary key)
- in 2NF
- contains no transitive dependencies (when one non-key field’s value depends on another non-key field’s value)
Source: from Beginning Database Design Solutions (Rod Stephens)
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