Partial string matching using patterns

Question

I need to write a query in R to match partial string in column names. I am looking for something similar to LIKE operator in SQL. For e.g, if I know beginning, middle or end

Answer 1

In regular expressions, ^ specifies the beginning of the string, $ specifies the end, thus:

y<- c("I am looking for a dog", "looking for a new dog", "a dog", "I am just looking")
grep("^looking.*dog$", y)
[1] 2

Answer 2

The grep function supports regular expressions and with regular expressions, you can match almost anything

y<- c("I am looking for a dog", "looking for a new dog", "a dog", "I am just looking")
grep("looking.*dog",y, value=T)
# [1] "I am looking for a dog" "looking for a new dog" 

Here this pattern looks for looking then "maybe something" then dog. So that should do what you want.