Of course you can just do what lex does, but if you use a good character class as the first character and thus eliminate backtracking back over the first character (for example, eliminate the optional part of [-+]?\d+ by making it into [-+\d]\d*) you can use the atomic match operator ?> to eliminate lots of backtracking, as you know that your SQL is well-formed, or rather, it's of little concern to you if the SQL is not well-formed.

Ideally, you have a disjunct set of character classes that start the separate matches. Likely, the disjunct set would be [-+\d] for numbers and ' for strings. If you want to be more careful, you can treat 0[bx]\w+ a bit more discerning, but I wouldn't bother and simply assume instead that the SQL is well-formed.

In reply to Re^3: In search of an efficient query abstractor by Corion
in thread In search of an efficient query abstractor by xaprb

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.