Where (or how) should I define the schema in a select statement when using PostgreSQL?

问题

I have an application built upon ASP.NET 3.5 and PostgreSQL 8.3. My database has 3 users, a data owner (xxx-owner), a data editor (xxx-editor), and a data viewer (xxx-viewer). Each user has their own schema called xxx-schema, xxx-editor-schema and xxx-viewer-schema. All the data is stored in xxx-schema.

This requires that I specify the schema when connecting to the database as either the xxx-editor or xxx-viewer users as shown in the following snippet.

NpgsqlCommand pgCommand = new NpgsqlCommand();
pgCommand.CommandText = @"SELECT 
                        bldg_id,
                        bldg_name,
                        bldg_no,
                        FROM " + this.schema + @".buildings
                        WHERE UPPER(bldg_id) LIKE UPPER(@id);";

pgCommand.Parameters.Add("@id", "%" + id + "%");
pgCommand.Connection = pgConnection;

If I were to follow this route I would specify the schema in the Web.config. However, there must be a better way to specify which schema should be used. I would like to be able to remove the string concatenation entirely if possible.

What is the best way to define the schema to be used in the SQL statement?

EDIT

The following from the PostgreSQL User Manual looks promising.

SearchPath - Changes search path to specified and public schemas.

From my limited testing it works alright in my situation. However, this is a PostgreSQL only solution. Is there perhaps a more database agnostic solution, do most databases provided such functionality?

EDIT 2

I've marked the answer below which lead me to changing the schema lookup order at the database level. With the following change I do not need to add code in my SQL statements.

ALTER USER xxx-viewer SET search_path TO '$user', xxx, public, sde

回答1:

You can set the schema search path on a per-session basis using:

SET search_path TO myschema

If you want to fall back to the public schema, you could use:

SET search_path TO myschema, public

回答2:

You also can do:

SET SCHEMA 'myschema';

This statement is the same that SET search_path TO myschema, public but more

来源：https://stackoverflow.com/questions/651527/where-or-how-should-i-define-the-schema-in-a-select-statement-when-using-postg

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ASP.NET

postgresql

schema

npgsql