Error while getting list of column names from a Firebird database table

Question

I tried several times to get a list of tables in firebird using python I tried this Get list of column names from a Firebird database table :

select rdb$field_name from rdb$relation_fields where rdb$relation_name=factura;

but didn't work it shows the error ('Error while preparing SQL statement:\\n- SQLCODE: -206\\n- Dynamic SQL Error\\n- SQL error code = -206\\n- Column unknown\\n- FACTURA\\n- At line 1, column 72', -206, 335544569)

Also tried using show table factura; but the I recibe the error ('Error while preparing SQL statement:\\n- SQLCODE: -104\\n- Dynamic SQL Error\\n- SQL error code = -104\\n- Token unknown - line 1, column 1\\n- show', -104, 335544569)

So, I dont know how to get this list of tables.

Answer 1

只有在 factura 是表的名称时才有效

Answer 2

Note: I have included the query into your answer as it makes it easier to answer.

You get the column unknown - FACTURA error because your where-clause is:

where rdb$relation_name=factura

Your unquoted use of factura makes it a column name of rdb$relation_fields , but no such column exists. This causes the error.

Instead you want to select rows whose rdb$relation_name column have the (string) value factura , that means you need to enclose it in single quotes (as was also shown in the accepted answer of the question you refer to ):

where rdb$relation_name='factura'

or, given case (in)sensitivity rules of column names:

where rdb$relation_name='FACTURA'

The reason show table factura doesn't work, is because that isn't part of the SQL syntax of Firebird, it only exists in the Firebird ISQL tool.

Answer 3

Also the table name must be uppercase, or no names will be found. Try:

select rdb$field_name
from   rdb$relation_fields
where  rdb$relation_name='FACTURA'
order by rdb$field_position;

The order by is optional. The single quotes and upper case table name are not.