GSQL matching using regular expression

[John_Chen]

Hi there,

I am trying to search for specific string pattern using regular expression using GSQL. It seems the best way is to define a UDF. Is there an example for doing so?

The only post I found relevant is the following where Richard Henderson was planning to blog about it.

Simple string concatenation

Is there any way to concatenate a string? The documentation mentions the + concat operator, but it doesn’t seem to be allowed: BEGIN CREATE QUERY searchSystem(VERTEX<system_> sys, STRING term) FOR GRAPH ty { f={sys}; songRes = SELECT s FROM f-(SA:sa)-A:a-(AB:ab)-C:c WHERE c.serch_col LIKE "%"+term+"%" LIMIT 10; PRINT songRes; } END The syntax error is saying it needs to be a literal or a variable. When I make it a variable, I still can’t assign it using string manipulation…

Thanks,
John

[Richard_Henderson]

Our published UDF library (the community one) has a regex searcher in it. I’d forgotten about that blog. Sorry about that. I have used the code in projects and it works well.

Concat should work into a variable assignment, though there can be some tricks needed. I’ll give it a go, and get back here.

[Richard_Henderson]

Okay, I did this and it worked:

CREATE QUERY test_concat(STRING in_val) FOR GRAPH test { 
  /* Write query logic here */ 
  STRING new_string ;
  
  new_string = "%"+in_val+"%";
  
  PRINT new_string; 
}