FG

Matching only the first occurrence in a line with Regex

Fresh3 days ago
Mar 15, 2026475486 views
Confidence Score1%
1%

Problem

I am completely new to regex and I would greatly appreciate any help. The task is simple. I have a CSV file with records that read like this: I would like to replace the first comma with a space and leave the rest of the commas intact, for every line. Is there a regex expression that will only match the first comma? I tried this: . This matches the comma, however, it also matches the entire length of the string preceding the comma, so if I try to replace this with a space all of the numbers are deleted as well.

Error Output

12345,67890,12345,67890
12345,67890,12345,67890
12345,67890,12345,67890
12345,67890,12345,67890
12345,67890,12345,67890

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Fix for: Matching only the first occurrence in a line with Regex

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The matching pattern could be: That means In e.g. perl, the whole match and replace would look like: The replacement part just takes the whole thing that matched and replaces it with the first block you remembered and appends a space. The coma is "dropped" because it's not in the first capturing group.

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