Add Fields to Existing Table in Version 10.5

[BruceonA5V10]

I've read the online help as best I could find, and checked the post here, but I can't find an example where you would be able to add one or more fields to an existing table.

An existing work File in spreadsheet mode is being first downloaded, then saved as a DBF file from Excel, after which, it will have to go through a series of manipulations to process some data each month. One of the first processes is to add a field name for updating with an update operation.
To first add the field, I tried the following in the interactive window:

table.open("workfile1",FILE_RW_EXCLUSIVE)

table.field_add("Product_Code","C",3)
ERROR: Use DB_CREATE_BEGIN first

So, this shows me that it wants me to create the table, but that is not what needs to be done.

How do I make this work my way?

Thanks,


Bruce

[Stan Mathews]

Re: Add Fields to Existing Table in Version 10.5

The TABLE.FIELD_ADD() method is used between the TABLE.CREATE_BEGIN() and TABLE.CREATE_END() methods to define the fields that form a table structure.

You want

A5_ADD_FIELDS_TO_TABLE()

[BruceonA5V10]

Re: Add Fields to Existing Table in Version 10.5

Ver good, I will work with that, I was sure I had seen something before on that.

[BruceonA5V10]

Re: Add Fields to Existing Table in Version 10.5

Ok, I got it in there this way

a5_add_fields_to_table("workfile1", "Product_Code,C,3")

What code should I use before I do this so as to check as make sure the field did not already exist?

[Stan Mathews]

Re: Add Fields to Existing Table in Version 10.5

tbl = table.open("workfile1",FILE_RW_EXCLUSIVE)
flds = tbl.field_name_get()
tbl.close()
if "Product_Code" $ flds
'do nothing
else
a5_add_fields_to_table("workfile1", "Product_Code,C,3")
end if

[CALocklin]

Re: Add Fields to Existing Table in Version 10.5

Danger Will Robinson!

If you happen to run this from a shadowed folder, the path to the full version of the table (on the server) should be specified. I haven't tested this on recent versions but I know that on some earlier versions of A5 this was definitely a problem. Here's the basic routine I use to handle that. (I ALWAYS use it even if I don't expect a workstation to be an issue. That way I never have to worry about it.)

DIM datapath as C
IF a5.Get_Master_Path() = ""
	datapath = a5.Get_Path()+chr(92)
ELSE
	datapath = a5.Get_Master_Path()+chr(92)
END IF

'---------------- Add new fields to rpt_main
table_namev = "rpt_main"
flist = a5_get_fieldnames( table_namev )
IF .not. ( ""$flist )	'2010-04-23
	new_list = <<%list%
FieldName,C,5,0
%list%
	a5_add_fields_to_table( datapath + table_namev + ".dbf", new_list )
END IF

One other warning (had to straighten someone out on this just last week) - DO NOT indent the field name. Even though the "new_list" variable is indented, the name of the field cannot be indented with tabs or spaces. The name of the field is just "FieldName" not "<tab>FieldName".

Any time you are using a crlf list (anything enclosed in the %..% tags), every line should start from the left edge. That is ALWAYS true. Sometimes the line should actually start with a space or tab but, since that's actually part of the line, the line is still starting from the left.

For a more complete explanation, try this post.