| Subject | RE: [firebird-support] Error while trying to add a primary key |
|---|---|
| Author | Helen Borrie |
| Post date | 2008-11-02T21:37:16Z |
At 03:43 AM 3/11/2008, you wrote:
It looks as if you need to get your hands on a native Firebird tool and extract, or at least properly inspect, the metadata of your database. At the very least, if you're relying on the presence of a constraint, you need to know which tables can be expected to return a result to this function. In isql (in Firebird's ..\bin\ directory) you can do a metadata extraction, but this does require an understanding of the data definition language (DDL). You'd get the info more easily with a free GUI utility tool such as Flamerobin (www.flamerobin.org) or IB_SQL (www.ibobjects.com). Both of these tools (along with many others you can find in the Contributed Downloads area at www.ibphoenix.com) use the native Firebird API and are not inhibited by generic interface limitations.
./heLen
>A query on RDB$INDICES returns this information about my table:No, the table doesn't have a primary key. This query result tells you that the index is unique (the fourth field) and that it is not system-defined (that's the zero fourth from the end). On an index created for a primary key constraint, that number would be > 0. Since Fb 1.5, named constraints would pass the name of the constraint as the name of the system-generated index; the default behaviour (and the only behaviour pre 1.5) is for the system to name the PK's index as RDB$PRIMARYnnnn (where the nnnn part is just an incrementing number).
>
>
>
>"PK_MEDIATYPE ", "MEDIATYPE ", 1, 1,
><Null>, 1, <Null>, <Null>, <Null>, 0, <Null>, <Null>, 0
>
>
>
>Given the index name, I assume there already is a Primary Key (PK) on this
>column, which is what I want.
>However, a call to SQLPrimaryKeys(), returns zero rows.The designer of your product probably wouldn't see it as a bug, as long as his software "works". It's likely the database was converted from some old ISAM database engine where a "primary key" is not implemented as a constraint but by reference to an associated file. It's not unusual for people doing such conversions for home-baked applications to assume that a unique index is "enough" to make a column behave like a constraint key.
>
>Thus, I'm going to have to report this as a bug.
> My program needs to know what the primary key field is, and that is the purpose of calling SQLPrimaryKeys().It's going to be a problem relying on knowing what a PK field is if you have tables that don't have any.
It looks as if you need to get your hands on a native Firebird tool and extract, or at least properly inspect, the metadata of your database. At the very least, if you're relying on the presence of a constraint, you need to know which tables can be expected to return a result to this function. In isql (in Firebird's ..\bin\ directory) you can do a metadata extraction, but this does require an understanding of the data definition language (DDL). You'd get the info more easily with a free GUI utility tool such as Flamerobin (www.flamerobin.org) or IB_SQL (www.ibobjects.com). Both of these tools (along with many others you can find in the Contributed Downloads area at www.ibphoenix.com) use the native Firebird API and are not inhibited by generic interface limitations.
./heLen