Re: Prefixed indexes

[Bruno ASTIER]

HI Jon,

Thanks for reply.


I understood that if SQL statement is valid then it is passed to engine,which will ignore prefixes in case of NDB. Right ?

But I'm still confused, are 'UNIQUE' indexes and 'PRIMARY KEY' subject to the same rule ? I mean, if statement is valid, does NDB engine should ignore prefixes ?

I have no chance with these :
- create table t (c1 int not null, c2 varchar(500), primary key (c2(50)))engine=ndb;
- create table t (c1 int not null, c2 varchar(500), unique index i1 (c2(50))) engine=ndb;
- create unique index i2 on t (c2(50));
- alter table t add unique index i3 (c2(50));

I always get this error back :
ERROR 1089 (HY000): Incorrect prefix key; the used key part isn't a string, the used length is longer than the key part, or the storage engine doesn't support unique prefix keys


Are these statements valid ?



Regards, Bruno.

PS : sorry for my bad English, hope you understand me