Databases
StackOverflow2013
Postsdbo
PO
 

Note that there are some explanatory texts on larger screens.

plurals
  1. PO
    primarykey
    data
    text
    <p>If you think your data as a tree structure (of n levels) and you need to replace the "underscore" for the "dash" character of the tree structure's keys, then you can try to solve this functionality using the library designed for: <a href="http://richhickey.github.io/clojure/clojure.walk-api.html" rel="nofollow noreferrer">clojure.walk</a> </p> <p>Actually <strong>clojure.walk</strong> brings a similar functionality <a href="http://richhickey.github.io/clojure/clojure.walk-api.html#clojure.walk/keywordize-keys" rel="nofollow noreferrer">keywordize-keys</a></p> <pre><code>(defn keywordize-keys "Recursively transforms all map keys from strings to keywords." {:added "1.1"} [m] (let [f (fn [[k v]] (if (string? k) [(keyword k) v] [k v]))] ;; only apply to maps (postwalk (fn [x] (if (map? x) (into {} (map f x)) x)) m))) </code></pre> <p>Then you only have to change the <a href="http://clojuredocs.org/clojure_core/clojure.core/keyword" rel="nofollow noreferrer">keyword</a> function for the clojure.string/<a href="http://clojuredocs.org/clojure_core/clojure.string/replace" rel="nofollow noreferrer">replace</a> function</p> <p>and this is the result:</p> <pre><code>(defn underscore-to-dash-string-keys "Recursively transforms all map keys from strings to keywords." {:added "1.1"} [m] (let [f (fn [[k v]] (if (string? k) [(clojure.string/replace k "_" "-") v] [k v]))] ;; only apply to maps (clojure.walk/postwalk (fn [x] (if (map? x) (into {} (map f x)) x)) m))) (underscore-to-dash-string-keys {"_a" 1 "_b" 2 "_c" 3}) =&gt; {"-a" 1, "-b" 2, "-c" 3} </code></pre> <p>Related to this question : <strong>How best to handle the mapping of Cassandra column names to Clojure variables?</strong> I think it is well discussed here <a href="https://stackoverflow.com/questions/9345056/in-clojure-how-to-destructure-all-the-keys-of-a-map">In Clojure, how to destructure all the keys of a map?</a></p>
    singulars
    1. This table or related slice is empty.
    1. POclojure-variable-names for database_column_names
      singulars
      1. PTQuestion
    1. PTAnswer
    1. USCommunity
    1. UStangrammer
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    1. COif the question were, how to transform the keys of a Cassandra result-set map from underscores to dashes, I'd do it this way: `(defn underscore-to-dash-string-keys[m] (into {} (for [[k v] m] [(clojure.string/replace k \_ \-) v])))`. but the question is, what's the idiomatic way to handle column names with underscores? If your answer is, "simply transform the underscores to dashes", then, as I said above, I think this obscures the underlying Cassandra implementation too much.
      singulars
      1. PO
      1. USChris Tennant
    2. COMy solution will also wrap the cassandra nested data structures (but actually i don't know if it can be a real case).
      singulars
      1. PO
      1. UStangrammer
    3. COand actually, you get keywords keys back from Cassandra, so my solution would need to be: `(defn underscore-to-dash-string-keys[m] (into {} (for [[k v] m] [(-> k name (clojure.string/replace \_ \-) keyword) v]))) `
      singulars
      1. PO
      1. USChris Tennant
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload