MySQL 8.0

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CREATE TABLE tab(id INT, CONSTRAINT unq_tab_id UNIQUE(id))
SELECT * FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS WHERE TABLE_NAME = 'tab'


CONSTRAINT_CATALOG
CONSTRAINT_SCHEMA
CONSTRAINT_NAME
TABLE_SCHEMA
TABLE_NAME
CONSTRAINT_TYPE
ENFORCED


def
fiddle
unq_tab_id
fiddle
tab
UNIQUE
YES


ALTER TABLE tab DROP CONSTRAINT unq_tab_id

Records: 0  Duplicates: 0  Warnings: 0


SELECT * FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS WHERE TABLE_NAME = 'tab'


CONSTRAINT_CATALOG
CONSTRAINT_SCHEMA
CONSTRAINT_NAME
TABLE_SCHEMA
TABLE_NAME
CONSTRAINT_TYPE
ENFORCED