tds-fdw / tds_fdw

A PostgreSQL foreign data wrapper to connect to TDS databases (Sybase and Microsoft SQL Server)
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IMPORT FOREIGN SCHEMA syntax error #210

Open mdlarussa opened 5 years ago

mdlarussa commented 5 years ago

version 2.0.0-alpha.3 There appears to be a trailing ")" in the query ....

postgres=# IMPORT FOREIGN SCHEMA information_schema FROM SERVER abcd1234 INTO public; ERROR: syntax error at or near ")" LINE 2: ) SERVER abcd1234 ^ QUERY: SELECT t.table_name, c.column_name, c.data_type, c.column_default, c.is_nullable, c.character_maximum_length, c.numeric_precision, c.numeric_precision_radix, c.numeric_scale, c.datetime_precision FROM INFORMATION_SCHEMA.TABLES t LEFT JOIN INFORMATION_SCHEMA.COLUMNS c ON t.table_schema = c.table_schema AND t.table_name = c.table_name WHERE t.table_type = 'BASE TABLE' AND t.table_schema = 'information_schema' ORDER BY t.table_name, c.ordinal_position ) SERVER abcd1234 OPTIONS (schema_name 'information_schema', table_name '');

mdlarussa commented 5 years ago

Trying to pull in the SQL Server information_schema in order to enumerate all columns within an instance. Command on SQL Server side: "select * from INFORMATION_SCHEMA.COLUMNS"

If I use dbo as schema name, import works, but of course the query fails.

juliogonzalez commented 5 years ago

I am pretty sure the problem is table_name '') (no value for table_name param).

Problem seems to be at https://github.com/tds-fdw/tds_fdw/blob/master/src/tds_fdw.c#L3155 (prev_table is null).

Wild guess: are you sure the user you configured for the USER MAPPING has access to INFORMATION_SCHEMA to list tables (and to access each of the tables)? Please verify it.

Of course, if that is the problem this would be still a bug.

On normal conditions, IMPORT SCHEMA works, we even have a test for it: https://github.com/tds-fdw/tds_fdw/blob/master/tests/tests/postgresql/003_import_schema.sql

jcarnu commented 5 years ago

This issue is the same than #219 :

Sorry for duplicating it, I'm working on it and testing the changes on my branch/repo.

It seems to work.

The problem is that INFORMATION_SCHEMAdoes not document itself with its views.

The query you use does return any table. The current source tries to list the columns of a null table. Leading to a mysterious error message with SERVER.

This issue will be soon closed.