postgresql_dump_extract.sh

#!/bin/sh

if [ $# -ne 2 ]
then
    echo "Usage: $0 <postgresql sql dump> <db_name>" >&2
	exit 1
fi

db_file=$1
db_name=$2

if [ ! -f $db_file -o ! -r $db_file ]
then
	echo "error: $db_file not found or not readable" >&2
	exit 2
fi

grep -b "^\connect" $db_file | grep -m 1 -A 1 "$db_name$" | while read line
do
	bytes=`echo $line | cut -d: -f1`

	if [ -z "$start_point" ]
	then
		start_point=$bytes
	else
		end_point=$bytes
	fi
done

if [ -z "$start_point" -o -z "$end_point" ]
then
	echo "error: start or end not found" >&2
	exit 3
fi

db_length=`expr $end_point - $start_point`

tail -c +$start_point $db_file | head -c $db_length | tail +3