问题
My odbc connection string for connecting to DB2i looks like this:
Driver={Client Access ODBC Driver (32-bit)};system=xx.xx.xx.xx;dbq=LIB1 LIB2 LIB3 LIB4 LIB5 LIB6 LIB7 LIB8;languageid=ENU;qrystglmt=-1;cmt=0;signon=1
The above connection string specifies multiple libraries/schemas for use. But when I try to access a file/table from a library other than the first one (like from LIB2...LIB8) I get a exception saying "FILE xx not found in LIB1"
Why does not it automatically search for the file/table in other specified libraries, it searches for the file in the first library only?
I need a workaround for this situation.
回答1:
Use "system naming" mode, by adding naming=1 to your connection string.
In your library list, place a comma before the first library.
Driver={Client Access ODBC Driver (32-bit)};system=systemname;naming=1;
dbq=,LIB1,LIB2,LIB3,LIB4,LIB5,LIB6,LIB7,LIB8;languageid=ENU;cmt=0;signon=1
回答2:
This works as documented in the manual:
The library list is used for resolving unqualified stored procedure calls and finding libraries in catalog API calls. ... Note: The first library listed in this property will also be the default library, which is used to resolve unqualified names in SQL statements.
回答3:
As stated above, Schema/library list is used to resolve functions/procedure names, not tables.
Let assume you need to read data from lib1.tab1 and lib2.tab2;
Here my personal workarounds (from easy to complex):
a) ask the db admin to have - for each table you need to use - the corresponding schema name, then do "select * from lib1.tab1 join lib2.tab2 on [...]" ;-) b) ask the db admin to create on schema "MyAlias" several alias (create alias) for each table you want to use. Then do "set current schema=MyAlias" followed by all the SQL statement you need e.g. "select * from tab1 join tab2". Since you’re querying myalias.tab1 which is an alias pointing to table lib1.tab1 it should work.
c) Complex: create your own SQL function that returns the corresponding schema_name for a table (e.g. myfunct('TAB1'). This could be done reading system view “qsys2.systables” where table_name=’TAB1’ and returning TABLE_SCHEMA column, which is a varchar(128). Once you got it, build up a dynamically prepared using the variable you just obtained. E.g. "set mylib = myfunct('TAB1'). "set mystmt = 'select * from '||table_schema || ‘.tab1’ …”
Prepare mystmt and then execute mystmt.
I did something similar in VBA using ado ibmdrda and it worked.
hope this helps.
f.
来源：https://stackoverflow.com/questions/20546385/specify-and-use-multiple-libraries-in-odbc-connection-string