Possible to make SQLite3::Statement#to_s more useful?

[sixtyfive]

Hi, after trying to debug something for a while and not being able to figure out how to see the SQL produced by sqlite3-ruby I'm now wondering why the following is the way it is:

qry = db.prepare("SELECT * FROM table WHERE a = ?")
qry.bind_params(123)
p qry.to_s # #<SQLite3::Statement:0x000055ed3b1d1f68>

An output like

SELECT * FROM table WHERE a = 123:

would be more helpful and expected.

[tenderlove]

On main, the output is like this:

irb(main):001> require "sqlite3"
=> true
irb(main):002> db = SQLite3::Database.new(":memory:")
=> 
#<SQLite3::Database:0x000000011dd805e0
...
irb(main):003> db.prepare "SELECT 1"
=> 
#<SQLite3::Statement:0x000000011dd603f8
 @columns=nil,
 @connection=
  #<SQLite3::Database:0x000000011dd805e0
   @authorizer=nil,
   @busy_handler=nil,
   @collations={},
   @default_transaction_mode=:deferred,
   @encoding=nil,
   @functions={},
   @readonly=false,
   @results_as_hash=nil,
   @tracefunc=nil,
   @type_translation=nil,
   @type_translator=#<Proc:0x000000011d8a84c8 /Users/aaron/git/sqlite3-ruby/lib/sqlite3/database.rb:747 (lambda)>>,
 @remainder="",
 @types=nil>
irb(main):004>

The gem throws away the SQL and bind params (after they're cast) because the statement doesn't need them anymore. We could modify the statement object to hold a reference, but that means the strings would live longer (IOW not get GC'd as quickly).

Is improving inspect output worth the cost of keeping (usually) unnecessary data around?

[sixtyfive]

When I wrote the issue, I was in the middle of a debugging session and really having difficulty figuring things out because the mental load was already high and working memory (my brain's, not the computer's) constantly at its limit. Reading your post, then mine again, I really do see your point. In production, SQLite is all about speed and efficiency. Perhaps this would need to be implemented as some sort of debugging flag. An environment variable switch, perhaps?

[tenderlove]

Perhaps this would need to be implemented as some sort of debugging flag. An environment variable switch, perhaps?

I think that's a good idea. We could do something like:

if $DEBUG
  @query = the_string
end

You can enable $DEBUG with a command line flag to Ruby (ruby -d script.rb).