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+---
+title: "Implementing Balance Sheets in PostgreSQL"
+Date: "2018-11-30"
+---
+### Example
+| Date | Title | Credit (+) | Debit (-) | Balance | 
+|--|--|--|--|--|
+| 2018-10-31 | Halloween Candy |  | 30 | -30 |
+| 2018-11-30 | Salary and Tax | 4000 | 200 | 3770 |
+| 2018-12-01 | Christmas Tree |  | 200 | 3570 |
+
+### Description
+Using balance sheets is a great way to keep track of assets and liabilities for both personal and business reasons. Spreadsheet software may be a good choice since it is simpler to access previous rows; however, this document entails the process of building a balance sheet in PostgreSQL in a simple manner. In this real-life example shown above, it is easy to interpret what the person has bought or where they have lost money and where they have gained money.
+
+### Code
+```sql
+CREATE TABLE public."BalanceSheet"
+             (
+                          "Date"       Date,
+				 		  "Title"      Text,
+                          "Credit (+)" NUMERIC,
+                          "Debit (-)"  NUMERIC,
+                          "Balance"    NUMERIC
+             );
+INSERT INTO "BalanceSheet"
+            (
+                        "Date",
+                        "Title",
+                        "Credit (+)",
+                        "Debit (-)",
+                        "Balance"
+            )
+            VALUES
+            (
+                        '2018-10-31',
+                        'Halloween Candy',
+                        0,
+                        30,
+                        0
+            )
+            ,
+            (
+                        '2018-11-30',
+                        'Salary and Tax',
+                        4000,
+                        200,
+                        0
+            )
+            ,
+            (
+                        '2018-12-02',
+                        'Christmas Tree',
+                        0,
+                        200,
+                        0
+            );
+
+WITH tt
+     AS (SELECT a."Date",
+                Sum(b."Credit (+)" - b."Debit (-)") Running_Total
+         FROM   "BalanceSheet" a,
+                "BalanceSheet" b
+         WHERE  ( b."Date" <= a."Date" )
+         GROUP  BY 1
+         ORDER  BY 1)
+UPDATE "BalanceSheet"
+SET    "Balance" = tt.running_total
+FROM   tt
+WHERE  tt."Date" = "BalanceSheet"."Date";
+
+SELECT *
+FROM   PUBLIC."BalanceSheet"
+ORDER  BY "Date" ASC; 
+```
+### Code Breakdown and Explanation
+*BalanceSheet* contains columns for date, title, credit, debit, and balance. This makes it easy to view and understand the table's contents.
+
+*tt* is a temporary table used to calculate *running_total* of all of the previous entries' separate balances until the current entry.
+>`Sum` is used to calculate this by subtracting the *Debits (-)* (money owed) from the *Credit (+)* (money gained) each month.
+
+>`GROUP BY` selects the data for aggregation (*running_total*).
+
+>`ORDER BY` sorts the data by *Date* so an accurate balance is calculated.
+
+>`WHERE` makes sure the *Balance* is only updated for the correct entry.
+
+Finally, the table is sorted by *Date* for easier interpretation using `ORDER BY`.