Progress
Programming
Handbook
Using the IMPORT Statement
The IMPORT statement is the counterpart of the EXPORT statement. It reads an input file into Progress procedures, one line at a time.
Using IMPORT to Read Standard Data
The following example shows IMPORT reading the file exported by the procedure
p-export.p
:
This relies on the input being space separated. You can also use the DELIMITER option of the IMPORT statement to read a file with a different separator.
For example,
p-imprt2.p
reads the file produced byp-exprt2.p
in the previous section:
This example reads one line at a time from
p-datfl7.d
into the character-string variable data. It then breaks the line into discrete values and assigns them to the fields of a customer record.Using IMPORT to Read Non-standard Data
Although the IMPORT statement is used primarily to read data in the standard format written by the EXPORT statement. However, you can use the UNFORMATTED and DELIMITER options of IMPORT to read data in non-standard formats.
When you use the UNFORMATTED option, the IMPORT statement reads one line from the input file. For example, suppose your input file is formatted as follows:
The lines containing cust–num and sales–rep values can be read with normal IMPORT statements. However, if you try to read the customer name values with a normal IMPORT statement, only the first word of each name is read—the space character is treated as a delimiter. To prevent this, read the name with the UNFORMATTED option, as in
p-impun1.p
.
Now, suppose each line of the file contained a cust–num, name, and sales–rep value, but no special delimiters are used. Instead, the fields are defined by their position within the line:
In
p-datfl3.d
, the first three character positions in each line are reserved for the cust-num value, the next 17 positions for the name value, and the last three for the sales-rep value. Space characters may occur between fields, but they may also occur within a field value. To process this file with the IMPORT statement, use the UNFORMATTED option to read one line at a time, as shown inp-impun2.p
:
After
p-impun2.p
reads each line, it uses the SUBSTRING function to break the line into field values. It then assigns these values to the appropriate fields in the customer record.NOTE: If a line in your input file ends with a tilde (~), Progress interprets that as a continuation character. This means, that line and the following line are treated as a single line. Therefore, the IMPORT statement with the UNFORMATTED option reads both lines into a single variable.What if fields values are separated by a delimiter other than the space character? For example, in
p-datfl4.d
, field values are separated by commas:
You could use the UNFORMATTED option of the IMPORT statement to read this file one line at a time and then use the INDEX function to locate the commas and break the line into field values. Another solution is to use the DELIMITER option of the IMPORT statement as shown in
p-impun3.p
:
In this example, the DELIMITER option specifies that field values are separated by commas rather than by spaces. Therefore, the IMPORT statement parses each line correctly and assigns each value to the appropriate field.
NOTE: You can only specify a single character as a delimiter. If the value you give with the DELIMITER option is longer than one character, then only the first character is used.For more information on the IMPORT statement, see the Progress Language Reference .
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