Doc: Fix incorrect parentheses in doc for find-by-keys

[conan]

I just tried the find-by-keys function for the first time following the docs:

(sql/find-by-keys db/ds :messages {:email "joe@bloggs.com"} {:columns [[:id]]})

I got this error:

Execution error (NullPointerException) at next.jdbc.sql.builder/safe-name (builder.clj:27).
Cannot invoke "clojure.lang.Named.getName()" because "x" is null

I changed {:columns [[:id]]} to {:columns [:id]} and it worked and returned me the results I needed. My observed behaviour is what I'd expect anyway, so I think it's just a typo.

[seancorfield]

This is incorrect.

Per the docs:

The default behavior is to return all the columns in each row. You can specify a subset of columns to return using the :columns option. It takes a vector and each element of the vector can be:

• a simple keyword representing the column name (:column-fn will be applied, if provided),
• a pair of keywords representing the column name and an alias (:column-fn will be applied to both, if provided),
• a pair consisting of a string and a keyword, representing a SQL expression and an alias (:column-fn will be applied to the alias, if provided).

The example in the docs has [[:email :address]] which means: select column email AS address

If you want just id then [:id] will select it. If you want id AS the_key then you want [[:id :the_key]]

[conan]

sorry, i misunderstood, thank you for the explanation