text import file structures

[H. Randy Thomas]

I am new to Alpha five, but an old hand at Dbase (I've had a license since Dbase II, and still have a Visual Foxpro license) My question concerns importing text files, and defining the file structures into which they are imported. Dbase and Foxpro used the append command with a SDF tag to import text files directly into the database. Once you defined your file structure for the database, you were through. Access does somewhat the same thing, if you define your table and then do an export, saving the export specification, you can use the export specification to import the text file into the datbase. I have not found the methodology to do this in Alpha 5V5--can anyone give me a hint?

[H. Randy Thomas]

RE: text import file structures

BTW, I forgot to mention that the text file I am trying to import is NOT delimited, and DOES NOT contain field names. It is a fixed record length ascii file dump, with each field having defined, specific lengths.

[Al Buchholz]

RE: text import file structures

From the control panel, click on the operations tab. Then click new and build an import or export operation.

There are multiple options to choose, but once defined you can reuse as needed.

Had you tried this before or is this what you are looking for?

[H. Randy Thomas]

RE: text import file structures

Thanks for the reply--but not exactly. I already have a table defined that has the proper structure--is there any way to move that table's structure definition into the "import card"? I don't relish the thought of having to reenter the field specs. One would think that the "suggest structure" option would look to an existing table, if defined for the import, for the field definitions.

[Vince McGinnis]

RE: text import file structures

Yes, just click on the save button (on the toolbar) and you will be asked to name the import spec. (operation in A5).

You can continue to use this same import operation from then on.

You then may want to use Action scripting to assign and run the import operation from a button on a form.

[Vince McGinnis]

RE: text import file structures

Oops, misread your post.

The answer is no...there is no real way to take a structure fron an existing table and create an import spec.

Sorry, that would be nice though.

[Vince McGinnis]

RE: text import file structures

Okay, give me one more stab at this answer.

I also have wanted to be able to do this.

But, here is a (not too cumbersome) work around.

Note, your table structure should have about 20 or more field to make this adventure worth while.

1. open up the table whose structure you would like to use as a basis for an import operation in "Design mode", like you were going to edit the structure.

2. Highlight all the rows and columns.

3. Press ctrl-c to copy the highlighted structure.
(for some reason the edit menu is grayed out)

4. open MS Word.

5. Paste the structure of the table into Word

6. You will notice if you do a "Reveal Codes" in Word, that the the Alpha Five table structure you copied is simply TAB delimited text.

However, the structure you copied is missing two (2) important columns of information needed for the ASCII Table Import Operation. Thry are:

a. Import (yes or no)
b. Offet (The starting point for each field)

So, to enter the "Import" column

(with reveal codes on in Word)

aa. Insert the "Import" column between the "fieldname" column and the "Type" column by inserting a TAB and the word "Yes" or "No". This will tell Alpha Five if you want to bring in the field data or not.

bb. Insert the "offset" column between the "Type" and the "Width" column by inserting a TAB and the starting position (number) of eash field.

The first field's offset is usually 1. Simply, add the first field's length to that number to get the offset for the second fields offset...and so on.

7. When you have this complete creating the import spec in Word. Highlight all the rows and columns.

8. Open up an empty Import card in A5

9. Paste the spec into the Import card.

10. Fill in the input (text) file's name. Fill in the output's (DBF) name.

11. Save and name your Import Operation



Note: this is easier to do than explain.

This job is a little easier if your trying to create a "Character Separated ASCII file" Import spec, because there is no "Offset".

[Selwyn Rabins]

RE: text import file structures








New Page 1




Here is an Xbasic function that does what you want. It will import a fixed
length ascii file into an existing table.
The ascii file must match the structure of the table. e.g. if the table has 3
fields:
firstname,c20
lastname,c30
state,c2

then the ascii file must have data starting in columns 1, 21 and 51
Here is sample usage:
a5_import_into_table("customers","c:\data\newcustomer.txt")
The function returns the number of records imported as a character string.
If, instead of actually doing the import, you want to see the Xbasic code that
gets generated do this:
code = a5_import_into_table("customers","c:\data\newcustomer.txt", .t.)
a5_show_variable(code)

function a5_Import_into_Table as
C (target_table as c , ascii_filename as c, show_code = .f. )
'DESCRIPTION:Imports a fixed length ascii file into an existing table. Ascii
file must match the structure of the table.
'LIMITATIONS:X



dim preamble as c
preamble = ""%code%
dim temp_table as c
dim temp_folder as c
temp_folder = file.temp_path_get()

temp_table = file.temp_path_get() + "TempImport" +remspecial(file.temp_create(""))
+ ".dbf"
import.type = 1
import.names = "none"
import.file = ascii_filename
import.db = temp_table
import.skip_lines = 0
import.skip_bytes = 0
import.field_sep = ""
import.record_sep = ""CR""LF""
import.text_qualifier = ""
import.record_len = __record_length__
import.rem_blanks = .F.
import.escape_newlines = .F.
import.fields = __field_count__
%code%


DIM count AS N
DIM fields AS C
DIM i AS N
DIM offset AS N
DIM reclength AS N


fields = table.external_field_name_get(target_table,"N|t|W|d")
count = line_count(fields)
dim a_fields[count] as p
a_fields.initialize_properties("name|type|width|dec",fields)
reclength = 0
offset = 1
for i = 1 to count

a_fields[i].spec = a_fields[i].name + "," + a_fields[i].type + "," + offset +
"," + a_fields[i].width + "," + a_fields[i].dec
a_fields[i].spec = "import.field" + i + " = " + quote( a_fields[i].spec)

a_fields[i].append_field = "append.m_field" + i + " = " + quote(a_fields[i].name)
a_fields[i].append_exp = "append.m_exp" + i + " = " + quote("@")+"+" +"file.filename_parse(temp_table,\"n\")"
+"+"+ quote("-"" + a_fields[i].name)

offset = offset + val(a_fields[i].width)
reclength = reclength + val(a_fields[i].width)
next i

preamble = stritran(preamble,"__field_count__",""+count)
preamble = stritran(preamble,"__record_length__",""+(reclength + 2) )


dim import_code as c
import_code = preamble + crlf() + a_fields.dump_properties("spec") + crlf() +
"import()" + crlf()

'a5_show_variable(import_code)


dim append_preamble as c
append_preamble = ""%code%
a_tbl = table.open(target_table)
dim start_recs as n
start_recs = a_tbl.records_get()
append.t_db = temp_table
append.m_key = ""
append.t_key = ""
append.m_filter = ""
append.t_filter = ""
append.type = "All"
append.m_count = __field_count__
%code%

append_preamble = stritran(append_preamble,"__field_count__",""+count)

dim append_code as c
append_code = append_preamble + crlf() + a_fields.dump_properties("append_field")
+ crlf() + a_fields.dump_properties("append_exp")

append_code = append_code + crlf() + ""%code%
append.t_count = 0
a_tbl.append()
dim end_recs as n
end_recs = a_tbl.records_get()
a_tbl.close()
if file.exists(temp_table) then
file.remove(temp_table)
end if
%code%


dim all_code as c
all_code = import_code + crlf() + append_code

if show_code = .t. then
a5_Import_into_Table = all_code
else
a5_Import_into_Table = ""
dim result as c
result = evaluate_template(all_code)
if result "" "" then
ui_msg_box("Error",result)
a5_Import_into_Table = ""
else
dim recs_imported as n
recs_imported = end_recs - start_recs
a5_Import_into_Table = "" + recs_imported
end if
end if


end function

[Selwyn Rabins]

RE: text import file structures

note.

to use this function, just create a new, empty function in the code editor and past this in.

be careful with word wrapping. when you paste, there may be a lot of erroneous line breaks. fix these up before saving the function.

[Vince McGinnis]

RE: text import file structures

Thanks Selwyn, the function works great!

[H. Randy Thomas]

RE: text import file structures

Thanks for the reply--I think you and Vince have grasped what I am trying to explain. However, I think the answer is as you have proposed--an Xbasic script. It would be nice in a future release for such a function to be included. To be truly user friendly, the import function would simply need an extra button that would say " use destination file spec for import file" or something like that. Until such a time, I guess one could create an export operation, reveal the Xbasic code, and copy the table structure into an import operation script (with some modifications) and get it to work that way.

[Selwyn Rabins]

RE: text import file structures

randy

i think you may be missing the point of the function.

i have added the function to the language, so it will be built into the next patch of a5.

it is very easy to use. you don't need to bother with low level xbasic code.

to use the function you just execute this xbasic (which could be in a button on a form, or from the interactive window etc.)

a5_Import_into_Table("customer","c:\newcustomers.txt")


where "customer" is the name of the table you want to import into, and "c:\newcustomers.txt" is your ascii file.

[H. Randy Thomas]

RE: text import file structures

Thanks!!--I'll try it, and I sincerely appreciate the help

I admit i'm a newbie, and quite rusty at writing / reviewing code.