Clarification about table creation

We got some internal feedback about the difficulties in cartodbfy'ing a
table. We also got some feedback telling us about the ambiguity of the
table creation need.

We want to make it clear and straightforward so that people don't find
roadblocks when following the examples.

doc/copy_queries.md

@@ -29,7 +29,9 @@ Composing a chunked POST is moderately complicated, so most developers will use
 
 ### Example
 
-For a table to be readable by CARTO, it must have a minimum of three columns with specific data types:
+#### Table preparation
+
+First of all, you'll need to have **a table with the right schema** to copy your data into. For a table to be readable by CARTO, it must have a minimum of three columns with specific data types:
 
 * `cartodb_id`, a `serial` primary key
 * `the_geom`, a `geometry` in the ESPG:4326 projection (aka long/lat)
@@ -37,20 +39,29 @@ For a table to be readable by CARTO, it must have a minimum of three columns wit
 
 Creating a new CARTO table with all the right triggers and columns can be tricky, so here is an example:
 
-    -- create the table using the *required* columns and a
-    -- couple more
-    CREATE TABLE upload_example (
-        the_geom geometry,
-        name text,
-        age integer
-    );
+```sql
+-- Create the table using the *required* columns and a couple more
+CREATE TABLE upload_example (
+    the_geom geometry,
+    name text,
+    age integer
+);
+
+-- adds the 'cartodb_id' and 'the_geom_webmercator'
+-- adds the required triggers and indexes
+SELECT CDB_CartodbfyTable(current_schema, 'upload_example');
+```
+
+you can get these queries executed directly through the SQL API this way, just by replacing the `{username}` and `{api_key}` by yours:
+
+```sh
+# Table creation
+curl -v "https://{user}.carto.com/api/v2/sql?api_key={api_key}&q=CREATE+TABLE+upload_example+(the_geom+geometry,name+text,age+integer)"
+
+# Cartodbfy table (optional, but allows for table registartion in Builder dashboard)
+curl -v "http://{user}.carto.com/api/v2/sql?api_key={api_key}&q=SELECT+CDB_CartodbfyTable(current_schema,'upload_example')"
+```
 
-    -- adds the 'cartodb_id' and 'the_geom_webmercator'
-    -- adds the required triggers and indexes
-    SELECT CDB_CartodbfyTable('upload_example');
-    
-    -- Note that CDB_CartodbfyTable is called differently if you have an organization user
-    -- SELECT CDB_CartodbfyTable('your_org_username', 'upload_example');
 
 Now you are ready to upload your file. Suppose you have a CSV file like this:
 
@@ -68,7 +79,7 @@ The `FROM STDIN` option tells the database that the input will come from a data
 
 To actually run upload, you will need a tool or script that can generate a chunked POST, so here are a few examples in different languages.
 
-### CURL Example
+#### CURL Example
 
 The [curl](https://curl.haxx.se/) utility makes it easy to run web requests from the command-line, and supports chunked POST upload, so it can feed the `copyfrom` end point.
 
@@ -90,7 +101,7 @@ To upload a larger file, using compression for a faster transfer, first compress
         "http://{username}.carto.com/api/v2/sql/copyfrom?api_key={api_key}&q=COPY+upload_example+(the_geom,+name,+age)+FROM+STDIN+WITH+(FORMAT+csv,+HEADER+true)"
 
 
-### Python Example
+#### Python Example
 
 The [Requests](http://docs.python-requests.org/en/master/user/quickstart/) library for HTTP makes doing a file upload relatively terse.