Replace variable value in first file based on records in second in Unix

Question

I have below files a) File A

<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<root xmlns="http://aaa/1.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema" version="2.0">
    <project name="source">
        <mapping name="m_Source">
            <parameter name="SQL_Query">select  * from $$SCHEMA_NAME."$$TABLE_NAME" where $$COL > $$VALUE and $CONDITIONS</parameter>
            <parameter name="CONDITIONS">Default</parameter>
        </mapping>
    </project>
</root>

b) File b

$$SCHEMA_NAME=test
$$COL=LOAD_DATETIME
$$TABLE_NAME=table1
$$VALUE=1234

I want to replace the values of $$SCHEMA_NAME , $$COL , $$TABLE_NAME, $$VALUE with the values mentioned in right ( i.e. test,DATETIME,table1,1234) in file a

thanks for your help!!

CWLiu · Accepted Answer · 2018-07-26 06:14:55Z

1

#!/bin/sh

while read line; do
  a=$(echo $line | awk -F'=' '{print $1}')
  b=$(echo $line | awk -F'=' '{print $2}')
  sed -i "s/$a/$b/" file_a
done < file_b

Brief explanation,

Read each line in file_b and assign the value which is left of equation to 'a', and right one to 'b'.
Use sed to substitute the value in 'a' to the value in 'b' in the file_a.

answered Jul 26, 2018 at 6:14

CWLiu

4,0531 gold badge13 silver badges14 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

bruce Over a year ago

Can you please let me know how to redirect the output to a different file ?

Collectives™ on Stack Overflow

Replace variable value in first file based on records in second in Unix

1 Answer 1

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related