Informix Error -170

Reasons / Common Causes

-170 is a simple type mismatch: logs can only be added to dbspaces, and the target of the attempted log-add operation was a blobspace instead.

1. An administrator attempting to add a logical log to a blobspace rather than a dbspace — the direct cause. Blobspaces have a fundamentally different internal page structure optimized for large-object storage, and logs simply aren't a supported use of that structure.
2. Naming conventions that don't clearly distinguish dbspaces from blobspaces, making it easy to target the wrong one when running a log-add command by name.
3. Automation or scripts selecting a target storage space without validating its type first — iterating through storage spaces without filtering by type can pick a blobspace by mistake.
4. Unfamiliarity with the distinction between dbspaces and blobspaces during routine log-space maintenance, especially for someone newer to the environment's storage layout.

Solutions / Resolution

1. Target a real dbspace for the log-add operation instead — correct the command to specify a dbspace, not a blobspace.
2. Adopt naming conventions that clearly distinguish blobspaces from dbspaces (a consistent prefix, for example) to reduce this class of mistake going forward.
3. For automation or scripts, validate storage-space type before attempting operations restricted to dbspaces, rather than assuming any storage space name is a valid target.
4. Document or clarify the dbspace/blobspace distinction for the team if this recurs due to unfamiliarity with the environment's storage layout.

Examples

The mistaken target

onspaces -a blobspace1 -l
-- -170: blobspace1 is a blobspace, not a dbspace — logs can't be
-- added here

Fix:

onspaces -a dbspace1 -l
-- dbspace1 is a genuine dbspace — this succeeds

Naming conventions that prevent the mistake

-- Clear naming distinguishes the two types at a glance:
dbspace_primary, dbspace_temp    -- dbspaces
blob_documents, blob_images      -- blobspaces

Diagnostic Checks

1. Confirm the type of the target storage space:

   onstat -d
   

   Review whether the space named in the failing command is actually a dbspace or a blobspace.
2. Review naming conventions for the environment's storage spaces, if this kind of mistake seems likely to recur.

Related Errors / Related Topics

• -162 — "ISAM error: Storage space does not exist." Another blobspace-specific naming condition, though about existence rather than type mismatch.
• -166 — "ISAM error: Storage space is full." The other blobspace-specific error in this range dealing with capacity mechanics rather than type restrictions.

Confirm the storage space's actual type before attempting a log-add operation — this is a quick, direct check that resolves the confusion immediately.