doc: add loc function

Signed-off-by: Máximo Cuadros <[email protected]>

Author: mcuadros

docs/using-gitbase/examples.md

@@ -42,7 +42,7 @@ FROM
 WHERE num > 1;
 ```
 
-##  Get the number of blobs per HEAD commit
+## Get the number of blobs per HEAD commit
 
 ```sql
 SELECT COUNT(commit_hash),
@@ -76,6 +76,22 @@ GROUP BY committer_email,
          repo_id;
 ```
 
+## Report of line count per file from HEAD references 
+
+```sql
+SELECT
+    LANGUAGE(file_path, blob_content) as lang,
+    SUM(JSON_EXTRACT(LOC(file_path, blob_content), '$.Code')) as code,
+    SUM(JSON_EXTRACT(LOC(file_path, blob_content), '$.Comments')) as comments,
+    SUM(JSON_EXTRACT(LOC(file_path, blob_content), '$.Blanks')) as blanks,
+    COUNT(1) as files
+FROM commit_files
+NATURAL JOIN refs
+NATURAL JOIN blobs
+WHERE ref_name='HEAD'
+GROUP BY lang;
+```
+
 ## Files from first 6 commits from HEAD references that contains some key and are not in vendor directory
 
 ```sql
@@ -201,4 +217,4 @@ To kill a query that's currently running you can use the value in `Id`. If we we
 
 ```sql
 KILL QUERY 168;
-```
+```

docs/using-gitbase/functions.md

@@ -14,7 +14,7 @@ To make some common tasks easier for the user, there are some functions to inter
 |`uast_xpath(blob, xpath) blob`| performs an XPath query over the given UAST nodes                                                                |
 |`uast_extract(blob, key) text array`| extracts information identified by the given key from the uast nodes                                       |
 |`uast_children(blob) blob`| returns a flattened array of the children UAST nodes from each one of the UAST nodes in the given array              |
-
+|`loc(path, blob) json`| returns a JSON map, containing the lines of code of a file, separated in three categories: Code, Blank and Comment lines |
 ## Standard functions
 
 These are all functions that are available because they are implemented in `go-mysql-server`, used by gitbase.