# INPUTS
```yaml
name: INPUTS
description: this defines a ETL / ELT block where every level two block with proper metadata (yaml) is treated as a step in the workflow
runs_as: ETL # the runs_as defines how the block shoud be treated
active: true # active if missing the is consider active, if false this block and all its child are ignored
```

## SALES
```yaml
name: SALES
table: sales
load_conn: "duckdb:" # Opens a DuckDB in-memory instance
load_before:
    - ATTACH 'postgres:@PG_CON' AS SRC (TYPE POSTGRES) #  Ataches data source as SRC in this case postgres OLTP DB, but could be any DBMS with a connecter / scanner
    - ATTACH 'ducklake:@DL_CON' AS TGT (DATA_PATH 's3://my-lakehouse_bucket...', ENCRYPTED) # Attaches target DB, TGT in this case a ducklake, prefirable, but again could be any DMBMS
load_validation: # Basic validation, normally used to check updates, avoid data duplication and unnessessary extractions (for more advanced conditional check use <step>_condition)
  - type: throw_if_empty # The processes will fail and be logged as such if the query returns empty
    sql: FROM SRC.<table> WHERE date_field = '{YYYY-MM-DD}' LIMIT 10 # The query that is executed
    msg: "The given date ({YYYY-MM-DD}) is not avaliable in the source!" # The message to be logged
    active: true
  - type: throw_if_not_empty # Fails if query return any row
    sql: FROM TGT.<table> WHERE date_field = '{YYYY-MM-DD}' LIMIT 10
    msg: "The date {YYYY-MM-DD} is already imported in the target, check to avoid duplications, or clean this period first!"
    active: true
load_sql: load_sales_data # Extracts from source and load on target in a sigle query thanks to duckdb capability of attaching different DBMS
load_on_err_match_patt: '(?i)table.+with.+name.+(\w+).+does.+not.+exist' # In case the load data query throws an error because the table is not created yet, in runs the sql in load_on_err_match_sql
load_on_err_match_sql: create_sales_table_instead # this sql only runs in case the load data fails and the error matchs the pattern in load_on_err_match_patt
load_after:
    - DETACH SRC # detaches the source DB
    - DETACH TGT # detaches the target DB
```
```sql load_sales_data
INSERT INTO TGT.<table> BY NAME
SELECT *
FROM SRC.<table>
WHERE date_field = '{YYYY-MM-DD}'
```
```sql create_sales_table_instead
CREATE TABLE TGT.<table> AS
SELECT *
FROM SRC.<table>
```
...