Create MySQL database name using variable from date

Question

for the variable

dbnya="echo $(date +%Y%m%d%H%M%S)"

When running below code, I will get an error (SQL syntax error)

mysql -u root -pthepass -e "CREATE DATABASE demo$dbnya CHARACTER SET utf8 COLLATE utf8_bin"

The second command will work if I'm using dbnya=20120423230524 as first command

Since your variables holds the string echo 2012042323524, the SQL command is CREATE DATABASE demoecho 2012042323524 CHAR... -- note the extraneous string "echo "

uther · Answer 1 · 2012-04-23 15:12:17Z

Use backticks instead of quotes.

dbnya=`echo $(date +%Y%m%d%H%M%S)`

The backtick (`) indicates the text is to be executed as a command, thus setting the variable to the output of the command.

stringbasic · Answer 2 · 2012-04-23 16:04:20Z

You don't need to use the echo command:

$> dbnya="echo $(date +%Y%m%d%H%M%S)"
$> echo $dbnya
echo 20120423170042

Just remove it from the command, dbnya will receive the result of the date evaluation:

$> dbnya="$(date +%Y%m%d%H%M%S)"
$> echo $dbnya
20120423170114

2 Answers