I want to create case-insensitive unique constraint for a column. But I am not able to figure out exact syntax for that.
I tried with this below ex query but getting syntax error.
alter table test_table_user add constraint user_name_unique unique (lower(user_name))
For case senstive there is collate option in spanner.
You can use same query just write column name as below
my_column COLLATE utf8_bin
document - https://cloud.google.com/spanner/docs/reference/standard-sql/collation-concepts#collate_operations