<p>InnoDB allows only one FULLTEXT index creation at a time; attempting more triggers error 1795.</p>
<p>MySQL Error 1795 ER_INNODB_FT_LIMIT appears when you try to create more than one InnoDB FULLTEXT index in a single operation. Run separate ALTER TABLE statements or merge columns into one index to resolve it.</p>
InnoDB presently supports one FULLTEXT index creation at
Error 1795 arises when a statement tries to create more than one InnoDB FULLTEXT index concurrently. InnoDB supports only one FULLTEXT index creation per statement or DDL transaction, so it halts the request and returns ER_INNODB_FT_LIMIT.
The error appears during CREATE TABLE, ALTER TABLE, or CREATE INDEX commands that specify multiple separate FULLTEXT indexes or when parallel sessions build indexes on the same table.
The failed DDL leaves the schema unchanged, blocks deployment pipelines, and prevents full-text search from working. Clearing the error lets migrations finish and search features operate.
The limitation exists because building a FULLTEXT index requires a full scan and tokenization of the table. Allowing multiple concurrent builds would consume excessive resources and risk corruption.
Rewrite the DDL so that each FULLTEXT index is created in its own statement, or combine all desired columns into a single multi-column FULLTEXT index, then rerun the migration.
Deployment scripts that add two separate FULLTEXT indexes fail - split them into sequential ALTER TABLE commands. ORMs that emit batched ADD FULLTEXT clauses need refactoring to one-at-a-time operations.
Plan FULLTEXT indexes during initial design, schedule index creation in low-traffic windows, and test migrations in Galaxy or a staging environment to catch the limit early.
ER_ILLEGAL_HA occurs when FULLTEXT is used on a non-InnoDB engine - switch to InnoDB. ER_TOO_MANY_KEYS happens when total index count exceeds limits - drop unnecessary indexes.
Using ALTER TABLE ... ADD FULLTEXT ft1(col1), ADD FULLTEXT ft2(col2) tries two indexes at once and triggers the limit.
Creating a FULLTEXT index in two concurrent sessions causes the second session to fail with ER_INNODB_FT_LIMIT.
Some migration tools group several FULLTEXT index definitions inside one ALTER TABLE statement, leading to the error.
Developers sometimes create separate indexes instead of a single multi-column FULLTEXT index that covers all needed columns.
Raised when FULLTEXT is attempted on an unsupported storage engine. Convert the table to InnoDB.
Occurs when an index key prefix is too long. Shorten the indexed columns or use prefix lengths.
Triggered when more than one PRIMARY KEY is defined. Remove redundant primary key definitions.
Yes. The limitation is per table, so you can build one FULLTEXT index per table at the same time across separate tables.
No. ER_INNODB_FT_LIMIT is specific to the InnoDB storage engine.
MySQL searches across all listed columns in the combined index. Use relevance ranking or boolean mode to refine results.
Galaxy flags multiple FULLTEXT index definitions in a single statement and suggests splitting them, preventing migration failures.
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