Why does $sql = <<EOSQL; require EOSQL to be in column 0?

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

I have this cgi that I build a sql statement in, pass to dbi and do stuff with the results. I want to make the code readable but the following complains if I indent the ending tag.

      $sql = <<EOSQL;
        update employee set
        fname = '$NS::fname',
        lname = '$NS::lname',
        team  = '$NS::team'
EOSQL  >- script complains if this is indented.
[download]

Why does EOSQL have to be in column 0 for the above assignment to work? Why can't it just read till it sees EOSQL?

TIA
Travis

2001-03-03 Edit by Corion : Changed PRE to CODE tags, fixed heredoc syntax.

Comment on Why does $sql = <<EOSQL; require EOSQL to be in column 0? Download Code

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Re: Why does $sql = EOSQL; require EOSQL to be in column 0? by yakko (Friar) on Feb 23, 2001 at 00:39 UTC
That's the nature of a "here" doc: the end of the doc has to be on the first column. But, according to this FAQ, you can have embedded spaces if you really want them. -- Me spell chucker work grate. Need grandma chicken.	[reply]
Re: Why does $sql = EOSQL; require EOSQL to be in column 0? by dws (Chancellor) on Feb 23, 2001 at 00:40 UTC
To indent, try `$sql = <<" EOSQL"; ... EOSQL` [download] Alternatively, you can break at the first blank line by doing `$sql = <<""; update employee set ...` [download] Though that's a bit controversial to some. Also, I suggest that you consider using bind parameters in the query. E.g., `update employee set fname = ?, lname = ?, team = ?` [download] and then pass the bindings to `execute()`.	[reply] [d/l] [select]
Re: Re: Why does $sql = EOSQL; require EOSQL to be in column 0? by dvergin (Monsignor) on Feb 23, 2001 at 00:55 UTC
Whenever you have variables in your heredoc, you will want to use double quotes in the example dws suggests. Otherwise the here doc will be single-quotish and the variables will not interpolate: `$sql = <<" EOSQL"; ... EOSQL` [download] This technique breaks of course if you change the indenting on the heredoc itself without changing the indent on the '<<' line. So you will need to decide if the readability is sufficient advantage to make up for the maintenance issue.	[reply] [d/l]
Re: Re: Re: Why does $sql = EOSQL; require EOSQL to be in column 0? by chipmunk (Parson) on Feb 23, 2001 at 08:33 UTC
FYI, if you leave off the quotes around your here-doc terminator, then you get the double-quotish, not single-quotish, behavior. To get a single-quotish here-doc, you have to explicitly use single quotes. `$name = 'Bob'; my $text = <<EOT; Hello, $name! EOT print $text;` [download]	[reply] [d/l]