Rails SQL：如何搜索表中的列而忽略所有特殊字符

Question

I am searching for matching values in MyTable.

name to search for -> This-is-a (test/with/time)
The name from DB table -> "this-is-a-test-with/time"

If I can get both the column value and the search value to match on something like this -> "thisisatestwithtime" which ignores all special characters and spaces.

value = This-is-a (test/with/time)
MyTable.where("upper(name) = upper(?)",value.to_s.scan(/[0-9a-z]/i).join("")).first

This converts the value to a form where all special characters are removed but how can I run the same on the value is in the table?

Answer 1

You can use a regular expression search.

select * from "table" where "name" ~ 'this' and name ~ 'is' and name ~ 'a' 
and name ~ 'test' and name ~ 'with' and name ~ 'time';

If you want to search whole words only (for example find -a- instead of cat )

name ~ '\ma\M'

For case insensitive, use

name ~* 'a'

https://www.postgresql.org/docs/9.6/static/functions-matching.html#FUNCTIONS-POSIX-REGEXP

You can also use replace to match the whole values

select * from table where regex_replace(name, '\W', '') = :name

Table.where("regex_replace(name, '\W', '') = :name", name: 'thisisatestwithtime')