How to Avoid ORA-01795: Alternatives to Multiple IN Clauses?

Alternative Approaches to Handle "ORA-01795: Maximum Expressions in a List Error"

When encountering the "ORA-01795: maximum number of expressions in a list is 1000 error," the standard advice is to modify the query and include multiple IN clauses as seen in the answer. However, let's explore another alternative method to work around this limitation.

One alternative is to use a temporary table, as seen in the following query:

CREATE TABLE temp_table AS
SELECT DISTINCT name
FROM table1
WHERE name IN ('value1', 'value2', ..., 'value10000+');

SELECT field1, field2, field3
FROM table1
WHERE name IN (SELECT name FROM temp_table);

DROP TABLE temp_table;

This method has the advantage of allowing the entire set of values to be used in a single IN clause, without the need to split it into multiple clauses. Additionally, it is reusable, as the temporary table can be kept for future queries.

While both approaches are effective in resolving the "ORA-01795" error, the choice between them depends on the specific requirements and constraints of the database environment.

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