README Update

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Yam ZhengLim
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Welcome to your new dbt project!
# DBT governance
Thid markdown document will specify the rules that need to follow by every developer.
<br>
Short naming converntion lists that need to follow
| model_type Shortcut | Full name |
| ------------------- | ------ |
| seed | Seed |
| src | Source |
| snap | Snapshot |
| stg | Stage |
| int | Intermediate |
| fct | Fact |
| dim | Dimension |
| rep | Report |
| sem | Semantic |
| model_name Shortcut | Full name | Use case |
| ------------------- | ------ | ------ |
| brg | Brigde | relationship table |
| log | Log | log data |
## CIEF General Rule
- Snowflake SQL use to write dbt SQL code
- Star schema is use
- First week of the day is start at Monday, and last week of the day will be Sunday
- Fiscal 1st quarter is start from Febuary
- Timezone: Kuala Lumpur / Malaysia (GMT +8)
- Some status/type is not input in raw database (You should found in seed)
<br/>
## DBT Rule
### Structure of the dbt folder model
- Analyses
1. Analyses model will not create in Snowflake
2. You can write some adhoc queries
3. test some SQL code before write in Models
<br/>
- Macros
1. Jinja function that reuse in other .sql / .py file
<br>
- Models
- Staging
1. Materialise: `View`
2. 1-to-1 relationship (or mapping) to source tables.
3. Column renaming
4. Column remove
5. Column data renaming, such as (status integer to string)
6. Data input error cleansing
7. Check for raw data freshness
8. Data type transformation
- Intermediate
1. Materialise: `Ephemerally`
2. Stacking layers of logic with clear and specific purposes to prepa our staging models to join into the entities we want
3. Be referenced repeatedly in more than one model
4. Isolating complex operations
- marts/warehouse
1. Store fact and dimension models
- marts/reporting
1. Store custom reports
- Seeds
- Snapshots
- Tests
### File Naming Rules
- File names must be unique
- Each sql/python file must start with [`model_type`]_[`system_name`]__[`model_name`]s.sql/py
- The model should be name as plural, (eg: stg_exchange__orders.sql)
### Column Naming Rules
- If array datatype, the column naming must be plural eg (ids, messages)
### SQL Coding Rule
- The SQL clause **must** be UPPERCASE (eg. `SELECT`, `FROM`, `WHERE`, `GROUP BY`, `LIMIT`, `WITH`, `AS`, `SUM`, `PARTITION OVER`, `DIV0`, `LEFT JOIN`, `ON` ....)
- Try to avoid using `EXCLUDE` in the SQL
- Avoid using multi layer subquery, and try to use CTE, subquery must not more than 1 layer
- Each model structure must contain with
```sql
--IMPORT
WITH [table_names] AS (
SELECT * FROM {{ ref('file_names')}}
),
--LOGIC
[logic_name] AS (
.....
),
--FINAL
final__[table_names] AS (
)
SELECT * FROM final__[table_names]
```
### Using the starter project
Try running the following commands:
- dbt run