Add example for projected spend (#90)

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

Author: mxr

README.md

@@ -170,3 +170,31 @@ ORDER BY
     , payee
 ;
 ```
+
+To count the spend for a category (ex: "Apps") between this month and the next 11 months (inclusive):
+
+```sql
+SELECT
+    budget_id
+    , SUM(amount_major) AS amount_major
+FROM (
+    SELECT
+        budget_id
+        , amount_major
+    FROM flat_transactions
+    WHERE
+        NOT deleted
+        AND category_name = 'Apps'
+        AND SUBSTR(`date`, 1, 7) = SUBSTR(DATE(), 1, 7)
+    UNION ALL
+    SELECT
+        budget_id
+        , amount_major
+    FROM scheduled_flat_transactions
+    WHERE
+        NOT deleted
+        AND category_name = 'Apps'
+        AND SUBSTR(date_next, 1, 7) < SUBSTR(DATE('now', '+1 year'), 1, 7)
+)
+;
+```

pyproject.toml

@@ -34,6 +34,15 @@ extend-select = [
 line_position = "leading"
 spacing_before = "touch"
 
+[tool.sqlfluff.rules.capitalisation.functions]
+extended_capitalisation_policy = 'upper'
+
+[tool.sqlfluff.rules.capitalisation.identifiers]
+extended_capitalisation_policy = 'lower'
+
+[tool.sqlfluff.rules.capitalisation.keywords]
+capitalisation_policy = 'upper'
+
 [tool.sqlfluff.rules.convention.terminator]
 multiline_newline = true
 require_final_semicolon = true