PostgreSQL raises error 42710 when you attempt to create or rename a database object to a name that already exists in the same schema.
PostgreSQL Error 42710 (duplicate_object) appears when you create or rename a table, index, sequence, or other object to a name already present in the target schema. Use IF NOT EXISTS, DROP, or ALTER RENAME to ensure the name is unique before rerunning the statement.
PostgreSQL Error 42710 (duplicate_object)
Error code 42710, condition name duplicate_object, means PostgreSQL found another object with the same name in the current schema. The conflict blocks CREATE, ALTER, or RENAME commands because each object name must be unique per namespace.
The server aborts the statement immediately.
No partial changes are committed, so your session remains consistent, but the intended object is not created or renamed.
The error arises during CREATE TABLE, CREATE INDEX, CREATE SEQUENCE, CREATE VIEW, CREATE TYPE, or similar commands when the chosen identifier already exists. It also fires when ALTER ... RENAME TO attempts to reuse an existing name.
Case-insensitive collisions trigger the error too because PostgreSQL folds unquoted identifiers to lowercase.
Attempting to create "Users" when "users" already exists will fail.
First, verify the conflicting name with \dt, \di, or querying pg_catalog.pg_class. Decide whether to reuse, drop, or rename the existing object.
Options include: 1) Drop the existing object if no longer needed; 2) Choose a new unique name; 3) Use CREATE ... IF NOT EXISTS to skip creation when it is already present; 4) Use ALTER ...
RENAME TO to change the old object before creating the new one.
Automated migrations often re-run CREATE statements. Guard them with IF NOT EXISTS to make migrations idempotent.
CI pipelines that parallelize tests may leave leftover tables. Add DROP TABLE IF EXISTS at the start or use transactional test setups that rollback.
Adopt naming conventions and prefixes per module to lower collision odds.
Track schema versions in migration tools such as Flyway or Liquibase.
Run CREATE operations inside explicit migration files reviewed in code review to catch duplicates early. Galaxy’s schema-aware autocomplete highlights existing object names, preventing typos that collide with live tables.
error 42P07 "duplicate_table" occurs specifically for existing tables; 42701 "duplicate_column" fires for column conflicts; 42712 "duplicate_alias" covers duplicate column aliases in the same SELECT list. Fixes follow the same inspect-then-rename pattern.
.
Occurs specifically for tables; message reads relation "name" already exists. Fix by using IF NOT EXISTS or renaming.
Triggered when adding a column that already exists in the table. Use ALTER TABLE ... DROP COLUMN or choose a new name.
Happens when two columns in a SELECT share the same alias. Rename one alias.
Raised during INSERT/UPDATE when unique constraints fail.
While different, it also signals duplicate data situations.
.
The failing statement is rolled back, but the outer transaction remains active unless you are in autocommit mode. You can correct the issue and continue.
Yes, PostgreSQL locks the catalog while checking existence, making IF NOT EXISTS atomic. However, if two sessions run the same CREATE simultaneously, only one succeeds.
PostgreSQL often includes the conflicting name in the message, like relation "users" already exists. If not, query pg_class and pg_type for the name.
Galaxy highlights the conflict before execution and suggests adding IF NOT EXISTS or renaming, but it does not automatically drop objects to avoid accidental data loss.
.avif)
.avif){kind=logo}
