Execute informix content from file - informix

Question

I need to execute a script (Informix code) in a .sql file for migration purposes. The thing is, I want to load it from a function to be able to use the exception, therefore being able to do a rollback in case of an error.
So, this is the code (still experimenting):
DROP FUNCTION IF EXISTS "informix".SCRIPT_MIGRATION();
CREATE FUNCTION "informix".SCRIPT_MIGRATION()
RETURNS BOOLEAN as RESULT;
DEFINE lv_execute lvarchar(32739);
DEFINE li_errnum, li_eisam INT;
DEFINE lv_errtxt CHAR(200);
ON EXCEPTION SET li_errnum, li_eisam, lv_errtxt
ROLLBACK;
CALL regista_log('script_migration', get_session_user(), li_errnum, lv_errtxt);
RETURN 'f';
END EXCEPTION;
CALL set_isolation_level();
BEGIN;
LET lv_execute = 'LOAD FROM ''C:\Users\Admin\Desktop\ConstaWeb_Stuff\test.sql'' DELIMITER ''+'' INSERT INTO SCRIPT_MIGRATION_TEMP_TABLE;';
DROP TABLE IF EXISTS SCRIPT_MIGRATION_TEMP_TABLE;
CREATE TABLE SCRIPT_MIGRATION_TEMP_TABLE(
STRING_TO_EXECUTE LVARCHAR(31739)
);
EXECUTE IMMEDIATE lv_execute;
COMMIT;
RETURN 't';
END FUNCTION;
CALL SCRIPT_MIGRATION();
That's because we apparently can't execute the load command inside functions. So I'm trying to execute it. But I'm not getting it right, apparently...
The objective here is to execute the script (not a shell command script! it's an Informix script, like creates, loads, unloads, drops...) on a file. I'm open to other ways of doing this.
I'm relatively new to Informix so I'm sure there is still a lot I don't know about it.

Answer 1

As already noted, the LOAD command is not a command recognized by the Informix server. Client products emulate an SQL statement by recognizing the syntax and reading the file and executing appropriate SQL statements. Changing the way you (try to) execute it in a function executing in the server will not help.
Using a shell script instead may help.
If you're migrating an existing Informix database to a new location (machine, version of Informix), then using DB-export and DB-Import may be a good way to go.
The DB-Access command is the 'standard' way to execute scripts from a shell script. You'd need to ensure you set the DBACCNOIGN environment variable to 1. That will then stop if there's an error during the LOAD and rollback the transaction. There's also the DB-Load command, but it will be harder to rollback DDL statements since it does not handle those.
Alternatively, you might find my SQLCMD* program useful — though it too isn't perfect. However, unlike DB-Access, it allows you to control which statements can generate errors that are ignored and which are not (continue [on|off|push|pop]; before and after as appropriate).
With careful packaging, you can use it to create your migration, assuming the DB-Export and DB-Import won't do the job for you automatically.
* You may have to subscribe to the IIUG to get at this. The registration is not onerous, and neither is the email load.