In Linux, how does one search for the content in a file? in linux, how does one search for the content?

In Linux, how does one search for the content in a file? in linux, how does one search for the content?

In Linux, how does one search and search for the content in a file? This should be the most common requirement in system maintenance and management. The following describes how to search and find the content in a file.

The grep command is commonly used to search and find the content in a file. In addition, the egrep and vi commands can also search for the content in the file.

1: search whether a file contains a string. Use grep "search content" filename1, for example

$ Grep ORA alert_gsp.log

$ Grep "ORA" alert_gsp.log

For example, you need to search for and find the characters in the utlspadv. SQL file that contain ORA.

[oracle@DB-Server admin]$ grep "ORA" utlspadv.sql

  --   ORA-XXXXX:        Monitoring already started. If for example you want 

  --   ORA-20111:

  --   ORA-20112:

  --   ORA-20113: 'no active monitoring job found'

  --   ORA-20113: 'no active monitoring job found'

  -- 0 |<PS> =>DBS2.REGRESS.RDBMS.DEV.US.ORACLE.COM 0 0 2 99.3% 0% 0.7% ""

  -- |<PR> DBS1.REGRESS.RDBMS.DEV.US.ORACLE.COM=> 100% 0% 0% "" |<PR> ...

  -- =>DBS2.REGRESS.RDBMS.DEV.US.ORACLE.COM 92 7 99.3% 0% 0.7% "" |<PR> ...

  -- |<C> CAPTURE_USER1=>DBS2.REGRESS.RDBMS.DEV.US.ORACLE.COM 2 0 0 0.E+00

  -- |<C> CAPTURE_USER1=>DBS2.REGRESS.RDBMS.DEV.US.ORACLE.COM

  -- ORA-20111:

  -- ORA-20112:

  --   ORA-20100:

  --   ORA-20113: 'no active monitoring job found'

  --   ORA-20113: 'no active monitoring job found'

[oracle@DB-Server admin]$ 

As shown above, this is a fuzzy match. In fact, I want to view errors such as ORA, so I want to filter out which ones are useless, modify the search content (you can also use special parameters, as described later), as shown below.

[oracle@DB-Server admin]$ grep "ORA-" utlspadv.sql

  --   ORA-XXXXX:        Monitoring already started. If for example you want 

  --   ORA-20111:

  --   ORA-20112:

  --   ORA-20113: 'no active monitoring job found'

  --   ORA-20113: 'no active monitoring job found'

  -- ORA-20111:

  -- ORA-20112:

  --   ORA-20100:

  --   ORA-20113: 'no active monitoring job found'

  --   ORA-20113: 'no active monitoring job found'

[oracle@DB-Server admin]$ 

2: If you want to search whether multiple files contain a certain string, you can use the following method:

Grep "search content" filename1 filename2.... filenamen

Grep "search content" *. SQL

For example, I want to check which SQL scripts in the current directory contain the view v $ temp_space_header (Note: if the search content contains special characters, it must be escaped, as shown below)

 

[oracle@DB-Server admin]$ grep "v\$temp_space_header" *.sql

catspacd.sql:drop public synonym v$temp_space_header;

catspacd.sql:drop public synonym gv$temp_space_header;

catspace.sql:create or replace view v_$temp_space_header as select * from v$temp_space_header;

catspace.sql:create or replace public synonym v$temp_space_header for v_$temp_space_header;

catspace.sql:create or replace view gv_$temp_space_header as select * from gv$temp_space_header;

catspace.sql:create or replace public synonym gv$temp_space_header

catspace.sql:            FROM gv$temp_space_header

[oracle@DB-Server admin]$ 

 

3: To display the number of lines in the search text file, you can use the-n parameter.

[oracle@DB-Server admin]$ grep  -n "v\$temp_space_header" *.sql

catspacd.sql:68:drop public synonym v$temp_space_header;

catspacd.sql:71:drop public synonym gv$temp_space_header;

catspace.sql:1952:create or replace view v_$temp_space_header as select * from v$temp_space_header;

catspace.sql:1953:create or replace public synonym v$temp_space_header for v_$temp_space_header;

catspace.sql:1956:create or replace view gv_$temp_space_header as select * from gv$temp_space_header;

catspace.sql:1957:create or replace public synonym gv$temp_space_header

catspace.sql:2357:            FROM gv$temp_space_header

[oracle@DB-Server admin]$ 

 

 

4: If you need to ignore case sensitivity during search, you can use the-I parameter.

[oracle@DB-Server admin]$ grep  "V\$TEMP_SPACE_HEADER" *.sql

[oracle@DB-Server admin]$ grep -i "V\$TEMP_SPACE_HEADER"  *.sql

catspacd.sql:drop public synonym v$temp_space_header;

catspacd.sql:drop public synonym gv$temp_space_header;

catspace.sql:create or replace view v_$temp_space_header as select * from v$temp_space_header;

catspace.sql:create or replace public synonym v$temp_space_header for v_$temp_space_header;

catspace.sql:create or replace view gv_$temp_space_header as select * from gv$temp_space_header;

catspace.sql:create or replace public synonym gv$temp_space_header

catspace.sql:            FROM gv$temp_space_header

[oracle@DB-Server admin]$ 

In addition, for example, check the installed MySQL component

[root@DB-Server init.d]# rpm -qa | grep -i mysql

MySQL-devel-5.6.23-1.linux_glibc2.5

MySQL-client-5.6.23-1.linux_glibc2.5

MySQL-server-5.6.23-1.linux_glibc2.5

 

 

5: Search for rows that do not match the specified string from the file content:

$ Grep-v "searched string" File Name

For example, when searching for some processes, we do not want to display the processes that contain the grep ora_mmon Command, as shown below:

[oracle@DB-Server admin]$ ps -ef  | grep ora_mmon  

oracle   16675 16220  0 00:09 pts/1    00:00:00 grep ora_mmon

oracle   21412     1  0 Aug22 ?        00:00:07 ora_mmon_gsp

[oracle@DB-Server admin]$ ps -ef  | grep ora_mmon  | grep -v grep

oracle   21412     1  0 Aug22 ?        00:00:07 ora_mmon_gsp

[oracle@DB-Server admin]$ 

6: search and find the matched rows:

$ Grep-c "searched string" File Name

[oracle@DB-Server admin]$ 

[oracle@DB-Server admin]$ grep   "v\$temp_space_header" *.sql

catspacd.sql:drop public synonym v$temp_space_header;

catspacd.sql:drop public synonym gv$temp_space_header;

catspace.sql:create or replace view v_$temp_space_header as select * from v$temp_space_header;

catspace.sql:create or replace public synonym v$temp_space_header for v_$temp_space_header;

catspace.sql:create or replace view gv_$temp_space_header as select * from gv$temp_space_header;

catspace.sql:create or replace public synonym gv$temp_space_header

catspace.sql:            FROM gv$temp_space_header

[oracle@DB-Server admin]$ grep -c  "v\$temp_space_header"  catspacd.sql

2

[oracle@DB-Server admin]$ grep -c  "v\$temp_space_header"  catspace.sql

5

[oracle@DB-Server admin]$ 

7: In some scenarios, we do not know the file type, or the file packages contain the strings we need to search for, so we can Recursively search all the files in a directory and subdirectory.

[Oracle @ DB-Server ~] $ Grep-r "v \ $ temp_space_header"/u01/app/oracle/product/11.1.0/dbhome_1/rdbms/admin/

/U01/app/oracle/product/11.1.0/dbhome_1/rdbms/admin/catspace. SQL: create or replace view v _ $ temp_space_header as select * from v $ temp_space_header;

/U01/app/oracle/product/11.1.0/dbhome_1/rdbms/admin/catspace. SQL: create or replace public synonym v $ temp_space_header for v _ $ temp_space_header;

/U01/app/oracle/product/11.1.0/dbhome_1/rdbms/admin/catspace. SQL: create or replace view gv _ $ temp_space_header as select * from gv $ temp_space_header;

/U01/app/oracle/product/11.1.0/dbhome_1/rdbms/admin/catspace. SQL: create or replace public synonym gv $ temp_space_header

/U01/app/oracle/product/11.1.0/dbhome_1/rdbms/admin/catspace. SQL: FROM gv $ temp_space_header

/U01/app/oracle/product/11.1.0/dbhome_1/rdbms/admin/catspacd. SQL: drop public synonym v $ temp_space_header;

/U01/app/oracle/product/11.1.0/dbhome_1/rdbms/admin/catspacd. SQL: drop public synonym gv $ temp_space_header;

[Oracle @ DB-Server ~] $

8: If you only want to retrieve the files that contain the searched content, run the following command:

[Oracle @ DB-Server ~] $ Grep-H-r "v \ $ temp_space_header"/u01/app/oracle/product/11.1.0/dbhome_1/rdbms/admin/| cut-d:-f1

/U01/app/oracle/product/11.1.0/dbhome_1/rdbms/admin/catspace. SQL

/U01/app/oracle/product/11.1.0/dbhome_1/rdbms/admin/catspace. SQL

/U01/app/oracle/product/11.1.0/dbhome_1/rdbms/admin/catspace. SQL

/U01/app/oracle/product/11.1.0/dbhome_1/rdbms/admin/catspace. SQL

/U01/app/oracle/product/11.1.0/dbhome_1/rdbms/admin/catspace. SQL

/U01/app/oracle/product/11.1.0/dbhome_1/rdbms/admin/catspacd. SQL

/U01/app/oracle/product/11.1.0/dbhome_1/rdbms/admin/catspacd. SQL

[Oracle @ DB-Server ~] $ Grep-H-r "v \ $ temp_space_header"/u01/app/oracle/product/11.1.0/dbhome_1/rdbms/admin/| cut-d:-f1 | uniq

/U01/app/oracle/product/11.1.0/dbhome_1/rdbms/admin/catspace. SQL

/U01/app/oracle/product/11.1.0/dbhome_1/rdbms/admin/catspacd. SQL

[Oracle @ DB-Server ~] $

9: If you only want to obtain the content that matches the entire search character, you can use the parameter w

You can compare the differences between the two.

[oracle@DB-Server admin]$ grep -w "ORA" utlspadv.sql

  --   ORA-XXXXX:        Monitoring already started. If for example you want 

  --   ORA-20111:

  --   ORA-20112:

  --   ORA-20113: 'no active monitoring job found'

  --   ORA-20113: 'no active monitoring job found'

  -- ORA-20111:

  -- ORA-20112:

  --   ORA-20100:

  --   ORA-20113: 'no active monitoring job found'

  --   ORA-20113: 'no active monitoring job found'

[oracle@DB-Server admin]$ grep  "ORA" utlspadv.sql

  --   ORA-XXXXX:        Monitoring already started. If for example you want 

  --   ORA-20111:

  --   ORA-20112:

  --   ORA-20113: 'no active monitoring job found'

  --   ORA-20113: 'no active monitoring job found'

  -- 0 |<PS> =>DBS2.REGRESS.RDBMS.DEV.US.ORACLE.COM 0 0 2 99.3% 0% 0.7% ""

  -- |<PR> DBS1.REGRESS.RDBMS.DEV.US.ORACLE.COM=> 100% 0% 0% "" |<PR> ...

  -- =>DBS2.REGRESS.RDBMS.DEV.US.ORACLE.COM 92 7 99.3% 0% 0.7% "" |<PR> ...

  -- |<C> CAPTURE_USER1=>DBS2.REGRESS.RDBMS.DEV.US.ORACLE.COM 2 0 0 0.E+00

  -- |<C> CAPTURE_USER1=>DBS2.REGRESS.RDBMS.DEV.US.ORACLE.COM

  -- ORA-20111:

  -- ORA-20112:

  --   ORA-20100:

  --   ORA-20113: 'no active monitoring job found'

  --   ORA-20113: 'no active monitoring job found'

[oracle@DB-Server admin]$ 

10: grep command combined with find command search

[oracle@DB-Server admin]$ find . -name '*.sql' -exec grep -i 'v\$temp_space_header' {} \; -print

create or replace view v_$temp_space_header as select * from v$temp_space_header;

create or replace public synonym v$temp_space_header for v_$temp_space_header;

create or replace view gv_$temp_space_header as select * from gv$temp_space_header;

create or replace public synonym gv$temp_space_header

            FROM gv$temp_space_header

./catspace.sql

drop public synonym v$temp_space_header;

drop public synonym gv$temp_space_header;

./catspacd.sql

[oracle@DB-Server admin]$ 

 

 

11: egrep-w-R 'word1 | word2 '~ /Klbtmp

12: The vi command can actually search the content in the file, but it is not as convenient and powerful as the grep command.

References:

Http://www.cyberciti.biz/faq/howto-search-find-file-for-text-string/