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Full Discussion: Shell Variables passed to awk to return certain rows
Top Forums Shell Programming and Scripting Shell Variables passed to awk to return certain rows Post 302948462 by Don Cragun on Monday 29th of June 2015 07:53:16 PM
Old 06-29-2015
You need a -v option for each variable you're setting; not just the first one.

If there is any chance that string_to_search could contain any whitespace characters or characters that have special meaning to the shell, it will also need to be quoted.

It is generally a good idea to quote all shell variable expansions, but I will assume for now that your script has already verified that $search_col_pos and $search_str_len expand to numeric strings.

And, inside an awk script, putting a variable name in quotes will try to match against the name of the variable instead of the contents of the variable.

Try:
Code:
awk -v search_col_pos=$search_col_pos -v search_str_len=$search_str_len -v string_to_search="$string_to_search" 'substr($0, search_col_pos, search_str_len) == string_to_search' test.txt

If that still doesn't work, show us what happens with the above corrections.
Last edited by Don Cragun; 06-29-2015 at 08:55 PM.. Reason: Fix typos.
This User Gave Thanks to Don Cragun For This Post:
pchang
 

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LEARN ABOUT PHP

pg_copy_from

PG_COPY_FROM(3) 														   PG_COPY_FROM(3)

pg_copy_from - Insert records into a table from an array

SYNOPSIS

       bool pg_copy_from (resource  $connection, string  $table_name, array  $rows, [string  $delimiter], [string  $null_as])

DESCRIPTION

       pg_copy_from(3) inserts records into a table from $rows. It issues a COPY FROM SQL command internally to insert records.

PARAMETERS

	      o $connection
		- PostgreSQL database connection resource.

	      o $table_name
		- Name of the table into which to copy the $rows.

	      o $rows
		-  An array of data to be copied into $table_name. Each value in $rows becomes a row in $table_name. Each value in $rows should be
		a delimited string of the values to insert into each field. Values should be linefeed terminated.

	      o $delimiter
		- The token that separates values for each field in each element of $rows. Default is TAB.

	      o $null_as
		- How SQL NULL values are represented in the $rows. Default is N ("\N").

RETURN VALUES

	Returns TRUE on success or FALSE on failure.

EXAMPLES

       Example #1

	      pg_copy_from(3) example

	      <?php
		 $db = pg_connect("dbname=publisher") or die("Could not connect");

		 $rows = pg_copy_to($db, $table_name);

		 pg_query($db, "DELETE FROM $table_name");

		 pg_copy_from($db, $table_name, $rows);
	      ?>

SEE ALSO

       pg_copy_to(3).

PHP Documentation Group 													   PG_COPY_FROM(3)
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