Move a file w/o changing timestamp using tar

tar -cf - ./filename | (cd other-directory; tar -xf -)

Not tested.

myisamchk notes

To speed up table repairing use large values for key buffer and sort buffer. Both values can be made very large cause only one of them is used at a time.

Eg: myisamchk --key_buffer_size=512M --sort_buffer_size=512M --read_buffer_size=8M --write_buffer_size=8M ./path/to/database/table.MYI

--sort-recover, -n

SCP example

from remote host to localhost

scp username@host:sourcefile targetfile

vice versa

scp sourcefile username@host:targetfile

Get events by date

select distinct date(A.TSTAMP) as DATES, count(A.TSTAMP) as HITS from EVENTS A, EPIC_CHRONICLES B where A.EVENTID = B.EVENTID group by DATES;

Runs very slowly at customer.

Remove last character from sql field.

update set = left(, length()-1);

Back Up mysql DB with Nice date format and compression.

mysqldump --user=$DB_USER --password=$DB_PASSWD --all-databases | bzip2 > $DB_BACKUP/01/mysql-`date +%Y-%m-%d`.bz2

Vim Backreferences

%s/\(\d\d:\d\d:\d\d\)'/\1/
this will remove single trailing quote from the end of time portion of timestamp.


%s/\(\.\)\(\w\+$\)/\t\2/
will change
com.epictide.upmc.service.impl.AlertByUserSummaryServiceImp
at end of line to
com.epictide.upmc.service.impl AlertByUserSummaryServiceImp
with a tab between the package and the class.



# convert camel case to DB table name format.
# put an underscore between each lower case followed by upper case character.
:%s/\([a-z]\)\([A-Z]\)/\1_\2/g

# make all character upper case
:%s/.*/\L&/g

Extract single file from zip on unix

unzip

This unzips file relative to current path.
Tutorial on unzip here:
http://www.linuxjournal.com/article/1324

Distinct on more that 2 fields

select distinct USERNAME, CLIENTNAME from MYTABLE order by USERNAME asc

Add/Subtract to/from date MySQL

update EVENTS set TSTAMP=DATE_SUB(TSTAMP, interval 9 month)

MySQL DB dump

mysqldump -u root -p -c --databases epictide events quartz >> dbdump.sql