| Bug #7092 | mysqldump adds quotes when called from shell script | ||
|---|---|---|---|
| Submitted: | 8 Dec 2004 1:25 | Modified: | 31 Jan 2005 23:20 |
| Reporter: | Matthew Lord | Email Updates: | |
| Status: | Not a Bug | Impact on me: | |
| Category: | MySQL Server: mysqldump Command-line Client | Severity: | S2 (Serious) |
| Version: | all | OS: | Linux (Linux) |
| Assigned to: | Guilhem Bichot | CPU Architecture: | Any |
[31 Jan 2005 22:23]
Guilhem Bichot
Created this script which is very much based on the provided testcase: #!/bin/sh BASE_DUMP_DIR=$1 #MYSQL_BIN=/usr/local/mysql-3.23.58-pc-linux-i686/bin MYSQL_SOCK=/tmp/mysql.sock MYSQL_USER=root MYSQL_DUMP=/m/mysql-4.1-clean/client/mysqldump DUMP_OPTS="--opt --fields-terminated-by='\t' --lines-terminated-by='\n' -S $MYSQL_SOCK -u $MYSQL_USER" echo "Running $MYSQL_DUMP $DUMP_OPTS -T $BASE_DUMP_DIR/test test" rm -f $BASE_DUMP_DIR/test/* # works fine $MYSQL_DUMP --opt --fields-terminated-by='\t' --lines-terminated-by='\n' -S $MYSQL_SOCK -u $MYSQL_USER -T $BASE_DUMP_DIR/test test # exhibits problem $MYSQL_DUMP $DUMP_OPTS -T $BASE_DUMP_DIR/test test Both $MYSQL_DUMP calls, tried one after the other, worked fine (both created files in test dir). Used mysqldump of latest 4.1 bk tree.
[31 Jan 2005 22:40]
Guilhem Bichot
Sorry, there was a misunderstanding and now I could repeat it.
[31 Jan 2005 23:20]
Guilhem Bichot
I'll assume customer is using bash - sh on Linux is usually a symlink to bash. The problem has nothing to do with mysqldump. As 'man bash' says: "Enclosing characters in double quotes preserves the literal value of all characters within the quotes". Consider this bash script: s1='hi'; echo $s1; s2="'hi'"; echo $s2; When executed, it prints: [guilhem 00:06 ~/tmp] sh ./7092bis hi 'hi' This is exactly what happens in the provided shell script: DUMP_OPTS="--opt --fields-terminated-by='\t' --lines-terminated-by='\n' -S $MYSQL_SOCK -u The fact to put a string in "" does some quoting. Consider this bash script: BASE_DUMP_DIR=$1 MYSQL_SOCK=/tmp/mysql.sock MYSQL_USER=root MYSQL_DUMP=/m/mysql-4.1-clean/client/mysqldump DUMP_OPTS="--opt --fields-terminated-by='\t' --lines-terminated-by='\n' -S $MYSQL_SOCK -u $MYSQL_USER" echo $MYSQL_DUMP --opt --fields-terminated-by='\t' --lines-terminated-by='\n' -S $MYSQL_SOCK -u $MYSQL_USER -T $BASE_DUMP_DIR/test test echo $MYSQL_DUMP $DUMP_OPTS -T $BASE_DUMP_DIR/test test (which does not call mysqldump, only echo), it prints: [guilhem 00:11 ~/tmp] sh ./7092bis /m/mysql-4.1-clean/client/mysqldump --opt --fields-terminated-by=\t --lines-terminated-by=\n -S /tmp/mysql.sock -u root -T /test test /m/mysql-4.1-clean/client/mysqldump --opt --fields-terminated-by='\t' --lines-terminated-by='\n' -S /tmp/mysql.sock -u root -T /test test Again, "'\t'" (which is what DUMP_OPTS is, if we simplify) is not the same as '\t'; "'\t'" means: " ["] is the string delimiter, treat ['] as a normal character" so ['] is passed down to program (echo or mysqldump). Whereas in '\t' the ['] is the string delimiter, so is not passed down to program (echo or mysqldump). The customer may want to change his script to: DUMP_OPTS="--opt --fields-terminated-by=\t --lines-terminated-by=\n -S $MYSQL_SOCK -u $MYSQL_USER" (removing the [']).
Description: #!/bin/sh BASE_DUMP_DIR=$1 MYSQL_BIN=/usr/local/mysql-3.23.58-pc-linux-i686/bin MYSQL_SOCK=/tmp/mysql323.sock MYSQL_USER=root MYSQL_DUMP=mysqldump DUMP_OPTS="--opt --fields-terminated-by='\t' --lines-terminated-by='\n' -S $MYSQL_SOCK -u $MYSQL_USER" echo "Running $MYSQL_DUMP $DUMP_OPTS -T $BASE_DUMP_DIR/test test" # works fine # $MYSQL_DUMP --opt --fields-terminated-by='\t' --lines-terminated-by='\n' -S $MYSQL_SOCK -u $MYSQL_USER -T $BASE_DUMP_DIR/test test # exhibits problem $MYSQL_DUMP $DUMP_OPTS -T $BASE_DUMP_DIR/test test When this script is invoked this is the statement that mysqld executes: SELECT /*!40001 SQL_NO_CACHE */ * INTO OUTFILE '/tmp/dumptest/for323/dumptest.txt' FIELDS TERMINATED BY '''\t''' LINES TERMINATED BY '''\n''' FROM `dumptest` How to repeat: create table dumptest (fname varchar(50), lname varchar(50)); insert into dumptest values ("matt", "lord"), ("lilu", "lord"), ("sidney", "lord"); Execute the shell script Suggested fix: We need to stop the addition of the quotes. The fact that the echo output looks correct points toward mysqldump being the cause.