How to fix shell bash mysql load query syntax error? - mysql

Question

I need a shell script to load data into mysql db. The script is the next:
# !bin/bash
qry="DROP TABLE IF EXISTS tmp_x;
CREATE TEMPORARY TABLE tmp_x AS SELECT * FROM x.y LIMIT 0;
LOAD DATA INFILE 'path/xxx.csv'
INTO TABLE tmp_x
FIELDS TERMINATED BY "\,"
ENCLOSED BY "\""
LINES TERMINATED BY "\\n"
IGNORE 1 ROWS;"
mysql --host=xxx --user=xxx --password=xxx db << EOF
$qry
EOF
I get the following error message:
ERROR 1064 (42000) at line 3: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the
right syntax to use near '
ENCLOSED BY "
LINES TERMINATED BY \n
IGNORE 1 ROWS' at line 3
I think it is something to do escaping some character, I tried changing to single quotes but it does not work neither.
I am workin on Ubuntu 18.
Any help will be very grateful.

Answer 1

Try this:
#!/bin/bash
mysql --host=xxx --user=xxx --password=xxx db << EOF
DROP TABLE IF EXISTS tmp_x;
CREATE TEMPORARY TABLE tmp_x AS SELECT * FROM x.y LIMIT 0;
LOAD DATA INFILE 'path/xxx.csv'
INTO TABLE tmp_x
FIELDS TERMINATED BY ','
ENCLOSED BY '"'
LINES TERMINATED BY '\\n'
IGNORE 1 ROWS;
EOF
If you really must use a variable, you'll need to play with quoting:
#!/bin/bash
qry="DROP TABLE IF EXISTS tmp_x;
CREATE TEMPORARY TABLE tmp_x AS SELECT * FROM x.y LIMIT 0;
LOAD DATA INFILE 'path/xxx.csv'
INTO TABLE tmp_x
FIELDS TERMINATED BY \",\"
ENCLOSED BY \"\\\"\"
LINES TERMINATED BY \"\\n\"
IGNORE 1 ROWS;"
mysql --host=xxx --user=xxx --password=xxx db << EOF
$qry
EOF

Answer 2

It can be troublesome to use double-quoted strings in your SQL, since you're using double-quotes as the string delimiter in bash. In other words, which is the double-quote that ends the bash string, and which should be treated as a literal double-quote character in the SQL?
To resolve this, use single-quotes for string delimiters in the SQL.
Another issue: There's no need to put a backslash before , for the field terminator.
Another issue: The \n needs another backslash.
Here's what I tried and it seems to work:
qry="DROP TABLE IF EXISTS tmp_x;
CREATE TEMPORARY TABLE tmp_x AS SELECT * FROM x.y LIMIT 0;
LOAD DATA INFILE 'path/xxx.csv'
INTO TABLE tmp_x
FIELDS TERMINATED BY ','
ENCLOSED BY '\"'
LINES TERMINATED BY '\\\n'
IGNORE 1 ROWS;"
I only printed the query, I haven't tested running it.