Comments are causing errors in MySQL Script

Question

I'm using -- and # for comments in my SQL scripts but when I run, it returns error messages about syntax errors. When I take the comments out it runs fine. For examples below cause errors.

#################################################
# DELETE RECORDS FROM TABLE
#################################################

-- DELETE RECORDS FROM TABLE WHERE EXTRACT RECORDS CONTAIN DELETE

The only comment I can do is # at the beginning of a line which I guess is sufficient but I want to know why this doesn't work. Did this all the time in SQLServer.

I don't know about any specific reason for # comments causing errors (I've had that same issue). But I recommend you change all your comments to -- to avoid any problems. — Barranka
– Barranka, Commented Jan 13, 2014 at 20:36
Yes, strange - # should work: dev.mysql.com/doc/refman/5.1/en/comments.html — Martin Wilson
– Martin Wilson, Commented Jan 13, 2014 at 20:39
Possible duplicate of stackoverflow.com/questions/6001390/… — Digital Chris
– Digital Chris, Commented Jan 13, 2014 at 20:47

lreeder · Accepted Answer · 2014-01-13 20:51:11Z

6

Both ways are acceptable for commenting out lines in MySQL scripts. See MySQL's documentation on comments. The hash at the start of the line is acceptable, as is the double-hyphen as long as it is followed by a space, e.g.:

-- This line is valid a comment

Not putting a space after the double hyphen will cause errors in mysql.

--This line is NOT a valid comment

If you are putting a space after the double-hyphens, there must be some other reason for the syntax errors. The example you posted works for me in MySQL without errors.

edited Jan 13, 2014 at 20:51

answered Jan 13, 2014 at 20:37

lreeder

12.3k2 gold badges60 silver badges68 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

Sander Over a year ago

The example works for me. The space-issue is something I encounter often (since it comments the line but is still read as an error). Please check this answer as correct @Bob

Ed Heal · Accepted Answer · 2014-01-13 20:37:01Z

1

Comments in SQL start -- i.e. What you have and that works

But not starting with '#'

So put -- to start a comment

This is when the database is running in ANSI mode (I guess)

answered Jan 13, 2014 at 20:37

Ed Heal

60.3k18 gold badges91 silver badges137 bronze badges

Comments

Yosoyke · Accepted Answer · 2014-01-13 20:37:30Z

0

Try to do this otherwhise..

-- #################################################
-- # DELETE RECORDS FROM TABLE
-- #################################################

-- DELETE RECORDS FROM TABLE WHERE EXTRACT RECORDS CONTAIN DELETE

answered Jan 13, 2014 at 20:37

Yosoyke

4854 silver badges12 bronze badges

Comments

Merlin · Accepted Answer · 2014-01-13 20:43:41Z

0

According to the documentation # is allowed for comments but you may need to add a space between the first and the second one eg: # ######

edited Jan 13, 2014 at 20:43

answered Jan 13, 2014 at 20:37

Merlin

4,9252 gold badges35 silver badges53 bronze badges

1 Comment

Martin Wilson Over a year ago

The OP is using MySQL

Collectives™ on Stack Overflow

Comments are causing errors in MySQL Script

4 Answers 4

1 Comment

Comments

Comments

1 Comment

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

4 Answers 4

1 Comment

Comments

Comments

1 Comment

Your Answer

Sign up or log in

Post as a guest

Linked

Related