2202G error code in PostgreSQL, labeled as
invalid_tablesample_repeat, indicates an issue with the
TABLESAMPLE clause, which is used to retrieve a subset of rows from a table randomly. This error occurs when the
REPEATABLE argument in the
TABLESAMPLE clause is not used correctly. The
REPEATABLE argument expects a seed value, which is a number that can be used to generate a pseudo-random sample that can be repeated in subsequent calls.
To diagnose and fix the
2202G error code, you should:
- Ensure that you are using the
- Check that the
REPEATABLEargument, if used, is followed by a numeric literal.
Here’s an example of how to use the
TABLESAMPLE clause correctly:
SELECT * FROM your_table TABLESAMPLE BERNOULLI (50) REPEATABLE (42);
In this example,
BERNOULLI (50) means that each row has a 50% chance of being included in the sample, and
REPEATABLE (42) means that the same pseudo-random sample can be selected again by using the same seed value
If you omit the
REPEATABLE argument or use a non-numeric value, you might encounter the
2202G error. Correct usage of the
REPEATABLE argument with a numeric literal will resolve this error.
TABLESAMPLE clause and the
REPEATABLE argument are specific to PostgreSQL, and their syntax or availability might differ in other database systems. Always consult the PostgreSQL documentation for the most accurate and detailed information regarding error codes and their resolutions.