Databases
StackOverflow2013
Postsdbo
PO
 

Note that there are some explanatory texts on larger screens.

plurals
  1. PO
    primarykey
    data
    text
    <p>I am sure regex and parseInt will perform well enough for you. However for your interest, I have compared it with a simple loop.</p> <pre><code>public static final Pattern DIGITS = Pattern.compile("(\\d+)"); public static void main(String[] args) { String text = "Some text before a number 123456 and some after"; for (int i = 0; i &lt; 5; i++) { timeRegex(text); timeLooping(text); } } private static int timeLooping(String text) { int ret = 0; final int runs = 1000; long start = System.nanoTime(); for (int r = 0; r &lt; runs; r++) { for (int i = 0; i &lt; text.length(); i++) { char ch = text.charAt(i); if (ch &lt;= '9' &amp;&amp; ch &gt;= '0') ret = ret * 10 + ch - '0'; else if (ret &gt; 0) break; } } long time = System.nanoTime() - start; System.out.printf("Took %,d ns to use a loop on average%n", time / runs); return ret; } private static int timeRegex(String text) { int ret = 0; final int runs = 1000; long start = System.nanoTime(); for (int r = 0; r &lt; runs; r++) { Matcher m = DIGITS.matcher(text); if (m.find()) ret = Integer.parseInt(m.group()); } long time = System.nanoTime() - start; System.out.printf("Took %,d ns to use a matcher on average%n", time / runs); return ret; } </code></pre> <p>prints</p> <pre><code>Took 19,803 ns to use a matcher on average Took 85 ns to use a loop on average Took 12,411 ns to use a matcher on average Took 83 ns to use a loop on average Took 8,199 ns to use a matcher on average Took 79 ns to use a loop on average Took 11,156 ns to use a matcher on average Took 104 ns to use a loop on average Took 4,527 ns to use a matcher on average Took 94 ns to use a loop on average </code></pre>
    singulars
    1. This table or related slice is empty.
    1. POOptimal regex to extract a single decimal number in an arbitrary string
      singulars
      1. PTQuestion
    1. PTAnswer
    1. This table or related slice is empty.
    1. USPeter Lawrey
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. POOptimal regex to extract a single decimal number in an arbitrary string
      singulars
      1. PTQuestion
    1. This table or related slice is empty.
    1. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTAcceptedByOriginator
    3. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    1. COWOW! I guess that answers @Bart Kiers's question which sadly reflects the mindset of "mainstream programming" nowadays.
      singulars
      1. PO
      1. USRegex Rookie
    2. CONever thought of myself as mainstream more special ... needs. ;)
      singulars
      1. PO
      1. USPeter Lawrey
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload