SQL Scratchpad¶

SQL Scratchpad is a SQL editor that lets you query ERD entity data directly in the browser.

SQL Scratchpad Editor Screen showing SQL editor, results grid, and notebook cells

How to Use¶

Open the Data Lab panel at the bottom of the ERD canvas, and select the SQL tab.

Executing Queries¶

Type SQL into the editor and press the Run button or Ctrl+Enter to display results in the grid below.

Supported SQL¶

Statement	Description	Example
`SELECT`	Data retrieval	`SELECT * FROM CUSTOMER`
`WHERE`	Condition filtering	`WHERE CUST_TYPE = 'VIP'`
`JOIN`	Table joins	`JOIN ORD ON CUSTOMER.CUST_NO = ORD.CUST_NO`
`GROUP BY`	Group aggregation	`GROUP BY CUST_TYPE`
`ORDER BY`	Sorting	`ORDER BY REG_DT DESC`
`INSERT`	Data insertion	`INSERT INTO CUSTOMER VALUES (...)`
`UPDATE`	Data modification	`UPDATE CUSTOMER SET ...`
`DELETE`	Data deletion	`DELETE FROM CUSTOMER WHERE ...`
`CREATE TABLE`	Table creation	`CREATE TABLE TEST (...)`

Mock Data (Sample Data)¶

To test actual queries, you need data. ThinkERD auto-generates sample data based on your ERD entity structure.

Data Generation Method¶

Drag and drop an entity from the canvas onto the Data Lab area to create its table and automatically populate it with mock data.

Column Type	Generated Data
`VARCHAR` (name)	Random names (e.g., "John Smith", "Jane Doe")
`VARCHAR` (code)	Random codes (e.g., "A001", "B002")
`INTEGER`	Random integers
`DECIMAL`	Random decimals (amounts, etc.)
`DATE`	Random dates
`BOOLEAN`	true/false

When you drop an entity, a menu appears:

Option	Action
DDL + Mock Data	Create table + insert sample data
DDL Only	Create table structure only (no data)
SELECT Query	Auto-generate a SELECT statement for the table

Notebook Mode¶

SQL Scratchpad supports managing multiple cells in a Notebook format.

Cell Management¶

Action	Method
Add cell	+ Add button at the bottom
Run cell	Individual cell's run button or `Ctrl`+`Enter`
Run all cells	Execute all cells sequentially
Delete cell	Delete button on the right side of the cell
Reorder cells	Drag and drop to rearrange

Usage Scenarios¶

Data Model ValidationReport Prototyping

Validate with SQL that the ERD entity structure meets business requirements.

-- Cell 1: Check order count per customer
SELECT c.CUST_NM, COUNT(o.ORD_NO) as order_count
FROM CUSTOMER c
LEFT JOIN ORD o ON c.CUST_NO = o.CUST_NO
GROUP BY c.CUST_NM;

-- Cell 2: Find customers with no orders (FK relationship verification)
SELECT c.CUST_NM
FROM CUSTOMER c
WHERE NOT EXISTS (
  SELECT 1 FROM ORD o WHERE o.CUST_NO = c.CUST_NO
);

Write actual report queries ahead of time to verify the data structure's suitability.

-- Monthly sales summary (report prototype)
SELECT
  EXTRACT(MONTH FROM o.ORD_DT) as month,
  SUM(o.ORD_AMT) as total_sales,
  COUNT(*) as order_count
FROM ORD o
GROUP BY EXTRACT(MONTH FROM o.ORD_DT)
ORDER BY month;

Data Reset¶

Revert data modified by query execution to its initial state.

Full reset — Delete all tables and data, restoring a clean state
Drop entities again to rebuild with fresh mock data

In-Browser Execution

SQL Scratchpad runs entirely in the browser. It does not connect to external databases, so you can safely test queries without affecting company data.