Merge Multiple INSERT Statements into One CSV

Merging Separate INSERT Statements

Database exports and seed files often contain multiple INSERT INTO statements for the same table rather than a single multi-row insert. This commonly happens when tools generate one INSERT per batch of rows or when data is appended incrementally.

Example SQL

CREATE TABLE employees (
  id INTEGER PRIMARY KEY,
  name VARCHAR(100),
  department VARCHAR(50),
  salary DECIMAL(10,2)
);

INSERT INTO employees (id, name, department, salary)
  VALUES (1, 'Alice', 'Engineering', 95000.00);
INSERT INTO employees (id, name, department, salary)
  VALUES (2, 'Bob', 'Marketing', 82000.00);
INSERT INTO employees (id, name, department, salary)
  VALUES (3, 'Charlie', 'Engineering', 105000.00);

Generated CSV

id,name,department,salary
1,Alice,Engineering,95000.00
2,Bob,Marketing,82000.00
3,Charlie,Engineering,105000.00

How Merging Works

The tool processes all INSERT INTO statements sequentially. When multiple statements target the same table:

1. Column names are determined by the first INSERT or the CREATE TABLE definition
2. All subsequent INSERT rows are appended to the same result set
3. If a later INSERT introduces new columns not seen before, they are added to the column list
4. Rows missing values for newly added columns get empty strings

This makes it trivial to consolidate fragmented database exports into a single, clean CSV file without manual editing.