ADO ConnectionString TextFile
This page is still a work in progress.
Text files files accessed via ADO will be read only. ADO does not have a driver that supports writing to or creating text files.
Arguments
The Provider supports the following arguments:
- FMT
- This argument tells ADO which delimiter is used for the file. Although the comma is probably the most widely-used delimiter for text files, it's not the only one. Another popular delimiter is the TAB.
Format | Description | Schema.ini Syntax | Connection String Syntax |
---|---|---|---|
Tab Delimited | Fields in the file are separated by tabs | Format=TabDelimited | FMT=TabDelimited |
CSV Delimited | Fields in the file are separated by commas (note that there should not be a space between the comma and the start of the next field name or value) | Format=CSVDelimited | FMT=CSVDelimited |
Custom Delimited | Fields in the file are separated by some character other than a tab or a comma (with one exception: you can't use the double-quote as a delimiter). For example, the asterisk is used as the delimiter | Format=Delimited(*) | FMT=Delimited(*) |
Fixed-Length | Fields in a file take up a specific number of characters. If a value is too long, "extra" characters are chopped off the end. If a value is too short, blank spaces are appended to it to make it fill out the requisite number of characters. The columns (fields) of the file need to be defined in a file named Schema.ini. |
Format=FixedLength | FMT=FixedLength |
- HDR
- Specifying HDR=YES means that the test file contains a header row. A header row simply means that the first row in the text file is a list of fields, with all subsequent rows containing the actual data.
Schema.ini
Schema.ini is simply a text file that tells ADO how to deal with your data file(s). This, by the way, is optional only when using a delimited file; if you have a fixed-length text file, you must use a Schema.ini file. In this file, you define the separator to be used (optional) and define the columns (fields) using syntax similar to this:
Coln=Fieldname Datatype <additional information>
Example:
Col1=FirstName Text Width 7 Col2=LastName Text Width 10 Col3=ID Text Integer 3
After you create the Schema.ini file, make sure you indicate in your script that the file does not use a header row. To do that, just set the HDR parameter to No.
A Separator.ini can hold information for many files. Hence you need to start each definition by the filename enclosed in square brackets e.g.:
[File_1.txt] Format=CSVDelimited [File_2.txt] Format=TabDelimited
Important: Schema.ini must be in the same folder as your text file.
Separator
With a delimited file, this often involves nothing more than telling ADO what the delimiter is:
[MyLog.txt] Format=TabDelimited
Data Types
You can use the following data types:
- Text
- Short
- Long
- Currency
- Single
- Double
- DateTime
- Memo