- Data Import
- Client APIs
- Data Types
- Window Functions
- Why DuckDB
- Code of Conduct
- Live Demo
Insert statements are the standard way of loading data into a relational database. When using insert statements, the values are supplied row-by-row. While simple, there is significant overhead involved in parsing and processing individual insert statements. This makes them very inefficient for bulk insertion.
As a rule-of-thumb, avoid insert into statements when inserting more than a few rows (i.e. avoid using insert into statements as part of a loop).
If you must use insert statements to load data in a loop, avoid executing the statements in auto-commit mode. After every commit, the database is required to sync the changes made to disk to ensure no data is lost. In auto-commit mode every single statement will be wrapped in a separate transaction, meaning
fsync will be called for every statement. This is typically unnecessary when bulk loading and will significantly slow down your program.
If you absolutely must use insert statements in a loop to load data, wrap them in calls to
An example of using
INSERT INTO to load data in a table is as follows:
CREATE TABLE people(id INTEGER, name VARCHAR); INSERT INTO people VALUES (1, 'Mark'), (2, 'Hannes');
A more detailed description together with syntax diagram can be found here.