Databases
StackOverflow2013
Postsdbo
POFastest way to replace multiple strings in a huge string
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POFastest way to replace multiple strings in a huge string
    primarykey
    data
    text
    <p>I m looking for the fastest way to replace multiple (~500) substrings of a big (~1mb) string. Whatever I have tried it seems that String.Replace is the fastest way of doing it.</p> <p>I just care about the fastest possible way. Not code readability, maintainability etc. I dont care if I need to use unsafe code or pre-process the original string either.</p> <p><strong>EDIT:</strong> After the comments I have added some more details:</p> <p>Each replace iteration will replace ABC on the string with some other string (different per replace iteration). The string to replace will ALWAYS be the same - ABC will always be ABC. Never ABD. So if there are <code>400.000</code> thousands replace iterations. The same string - ABC - will be replaced with some other (different) string each time. </p> <p>I can be in control on what ABC is. I can make it super-short or super-long as long as it doesn't affect the results. Clearly ABC can't be <em>hello</em> cause hello will exist as a word in most of the input strings.</p> <p>Example input: <code>ABCDABCABCDABCABCDABCABCDABCD</code></p> <p>Example replace from string: <code>BC</code></p> <p>Example replace with strings: <code>AA, BB, CC, DD, EE (5 iterations)</code></p> <p>Example outputs:</p> <pre><code>AAADAAAAAADAAAAAADAAAAAADAAAD ABBDABBABBDABBABBDABBABBDABBD ACCDACCACCDACCACCDACCACCDACCD ADDDADDADDDADDADDDADDADDDADDD AEEDAEEAEEDAEEAEEDAEEAEEDAEED </code></pre> <p><strong>Average case:</strong> Input string is 100-200kb with 40.000 replace iterations. Worst case: Input string is 1-2mb with 400.000 replace iterations.</p> <p>I can do ANYTHING. Do it in parallel, do it unsafe, etc. It doesnt matter how I do it. What matters is that it needs to be as fast as it gets.</p> <p>Thanks</p>
    singulars
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. USchue x
    1. USYannis
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    2. PO
      singulars
      1. PTAnswer
    3. PO
      singulars
      1. PTAnswer
    1. VO
      singulars
      1. POFastest way to replace multiple strings in a huge string
      1. This table or related slice is empty.
      1. VTApproveEditSuggestion
    2. VO
      singulars
      1. POFastest way to replace multiple strings in a huge string
      1. This table or related slice is empty.
      1. VTUpMod
    3. VO
      singulars
      1. POFastest way to replace multiple strings in a huge string
      1. This table or related slice is empty.
      1. VTUpMod
    1. COYou could look at handling chunks at a time, but String.Replace would be the way to go. Can you give us more context?
      singulars
      1. POFastest way to replace multiple strings in a huge string
      1. USliquidsnake786
    2. COWhat would you like to know? Imagine a big string. I can be in control of the format/length of sub-strings to replace (e.g. #abc# instead of abc or 123 etc). But this is an operation that will happen thousands of times on the same string with the same keys but different replacement values.
      singulars
      1. POFastest way to replace multiple strings in a huge string
      1. USYannis
    3. COGive us an example with input and expected output.
      singulars
      1. POFastest way to replace multiple strings in a huge string
      1. USAhmed KRAIEM
 

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