Hi, Does anyone have a configuration file for MySQL.
Thanks Jim ----- Original Message ----- From: "Michael Wang" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Thursday, November 14, 2002 11:22 PM Subject: URI limited to 255 in MySQL and DB2? > I found that URI column in OBJECTS and REVISIONS tables are limited > to 255 chars in MySQL and DB2, due to the primary key constraint. > > The purpose of this posting is to confirm this, and to seek opinions and > workaround. > > Thanks. > > (1) MySQL > > Copied from JDBC How To: > > " > create table objects(uri blob not null, primary key uriIndex (uri(255)), > classname blob); > " > > I believe PRIMARY KEY is used to enforce uniqueness as well as indexing. > If this is true, URI exceeds 255, and PRIMARY KEY is only done on the > first 255 chars, then the uniqueness is not enforced. > > The key is limited to 255 on a single column in MySQL (both MyISAM and > innoDB), having a larger URI column only create a hidden problem. It is > better to make the problem up front. For this reason, I would suggest > changing above to > > " > create table objects(uri varchar(255) not null, primary key uriIndex (uri(255)), > classname blob); > " > > How do you think? And anyone has an idea to make URI beyond 255 in MySQL? > > (2) DB2 > > The DB2 (version 7.1) has the same limitation on the length of > column with primary key, as shown below. > > " > db2 => create table obj(uri varchar(256) not null primary key, > db2 (cont.) => classname varchar(3200)); > > SQL20075 The index or index extension "SQL021114150625950" cannot be created > or altered because the length of "URI" is more than 255 bytes. SQLSTATE=54008 > > db2 => create table obj(uri blob(256) not null primary key, > db2 (cont.) => classname varchar(3200)); > > SQL0350N LOB, DATALINK, or structured type column "URI" cannot be used in an > index, a key, a unique constraint, a generated column, or a declared temporary > table. SQLSTATE=42962 > " > > Is there a way to go beyond 255 in DB2? > > Anyone has encountered the limitation in these two databases, and > has found a workaround? > > -- > Michael Wang > http://www.unixlabplus.com/ > > -- > To unsubscribe, e-mail: <mailto:slide-user-unsubscribe@;jakarta.apache.org> > For additional commands, e-mail: <mailto:slide-user-help@;jakarta.apache.org> > -- To unsubscribe, e-mail: <mailto:slide-user-unsubscribe@;jakarta.apache.org> For additional commands, e-mail: <mailto:slide-user-help@;jakarta.apache.org>
