fix(db_sqlite): self-heal cached db on integrity and data errors

insert(), replace() and delete() now delete and rebuild the cache database on sqlite3.IntegrityError and sqlite3.DataError (gated by delete_db_on_operational_error), not only on OperationalError. A schema change between releases (for example a NOT NULL column the caller no longer writes) previously raised an IntegrityError that fell through to the generic handler, so the stale database kept failing on every run until it was removed by hand.

Author: markuslf

CHANGELOG.md

@@ -8,7 +8,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
-tbd
+### Fixed
+
+* db_sqlite.py: cached databases now self-heal after a schema change between releases. A constraint or data error (such as a `NOT NULL` column that a newer or older release no longer writes) deletes and rebuilds the cache on the next run, instead of failing on every run until the stale file is removed by hand.
 
 
 ## [v5.0.0] - 2026-06-12

db_sqlite.py

@@ -28,7 +28,7 @@
 """
 
 __author__ = 'Linuxfabrik GmbH, Zurich/Switzerland'
-__version__ = '2026060201'
+__version__ = '2026061701'
 
 import csv
 import hashlib
@@ -355,7 +355,8 @@ def create_index(
       If `True`, creates a unique index.
       If `False`, creates a standard (non-unique) index. Defaults to `False`.
     - **delete_db_on_operational_error** (`bool`, optional):
-      If `True`, deletes the database file when an `OperationalError` occurs.
+      If `True`, deletes the database file when the on-disk database turns out
+      to be unusable (e.g. a schema mismatch between releases).
       Defaults to `True`.
 
     ### Returns
@@ -467,7 +468,8 @@ def cut(conn, table='perfdata', _max=5, delete_db_on_operational_error=True):
     - **_max** (`int`, optional):
       Number of most recent records to keep. Defaults to `5`.
     - **delete_db_on_operational_error** (`bool`, optional):
-      If `True`, deletes the database file when an `OperationalError` occurs.
+      If `True`, deletes the database file when the on-disk database turns out
+      to be unusable (e.g. a schema mismatch between releases).
       Defaults to `True`.
 
     ### Returns
@@ -530,7 +532,8 @@ def delete(conn, sql, data=None, delete_db_on_operational_error=True):
       Dictionary of parameters to bind to the SQL statement.
       Defaults to an empty dict (no parameters).
     - **delete_db_on_operational_error** (`bool`, optional):
-      If `True`, deletes the database file when an `OperationalError` occurs.
+      If `True`, deletes the database file when the on-disk database turns out
+      to be unusable (e.g. a schema mismatch between releases).
       Defaults to `True`.
 
     ### Returns
@@ -563,6 +566,14 @@ def delete(conn, sql, data=None, delete_db_on_operational_error=True):
         if delete_db_on_operational_error:
             rm_db(conn)
         return False, f'Operational Error: {e}, Query: {sql}, Data: {data}'
+    except (sqlite3.IntegrityError, sqlite3.DataError) as e:
+        # A constraint or data error (e.g. a NOT NULL column that a newer or
+        # older release no longer writes) means the on-disk schema no
+        # longer matches the data being written. Deleting the database lets the
+        # next run rebuild a valid cache from scratch.
+        if delete_db_on_operational_error:
+            rm_db(conn)
+        return False, f'Integrity Error: {e}, Query: {sql}, Data: {data}'
     except Exception as e:
         return False, f'Query failed: {sql}, Error: {e}, Data: {data}'
 
@@ -906,7 +917,8 @@ def insert(conn, data, table='perfdata', delete_db_on_operational_error=True):
       Name of the table to insert into.
       Defaults to `'perfdata'`.
     - **delete_db_on_operational_error** (`bool`, optional):
-      If `True`, deletes the database file when an `OperationalError` occurs.
+      If `True`, deletes the database file when the on-disk database turns out
+      to be unusable (e.g. a schema mismatch between releases).
       Defaults to `True`.
 
     ### Returns
@@ -946,6 +958,14 @@ def insert(conn, data, table='perfdata', delete_db_on_operational_error=True):
         if delete_db_on_operational_error:
             rm_db(conn)
         return False, f'Operational Error: {e}, Query: {sql}, Data: {data}'
+    except (sqlite3.IntegrityError, sqlite3.DataError) as e:
+        # A constraint or data error (e.g. a NOT NULL column that a newer or
+        # older release no longer writes) means the on-disk schema no
+        # longer matches the data being written. Deleting the database lets the
+        # next run rebuild a valid cache from scratch.
+        if delete_db_on_operational_error:
+            rm_db(conn)
+        return False, f'Integrity Error: {e}, Query: {sql}, Data: {data}'
     except Exception as e:
         return False, f'Query failed: {sql}, Error: {e}, Data: {data}'
 
@@ -1030,7 +1050,7 @@ def per_second_deltas(filename, name, counters):
     # subsequent drop_table() with "Cannot operate on a closed database".
     ok, _ = insert(conn, row, delete_db_on_operational_error=False)
     if not ok:
-        # Schema mismatch from a previous plugin version (different counter
+        # Schema mismatch from a previous release (different counter
         # columns or NOT NULL constraints). Rebuild the table from the
         # current schema; we lose the previous baseline but auto-recover on
         # the next run.
@@ -1130,7 +1150,8 @@ def replace(conn, data, table='perfdata', delete_db_on_operational_error=True):
       Name of the table to operate on.
       Defaults to `'perfdata'`.
     - **delete_db_on_operational_error** (`bool`, optional):
-      If `True`, deletes the database file when an `OperationalError` occurs.
+      If `True`, deletes the database file when the on-disk database turns out
+      to be unusable (e.g. a schema mismatch between releases).
       Defaults to `True`.
 
     ### Returns
@@ -1169,6 +1190,14 @@ def replace(conn, data, table='perfdata', delete_db_on_operational_error=True):
         if delete_db_on_operational_error:
             rm_db(conn)
         return False, f'Operational Error: {e}, Query: {sql}, Data: {data}'
+    except (sqlite3.IntegrityError, sqlite3.DataError) as e:
+        # A constraint or data error (e.g. a NOT NULL column that a newer or
+        # older release no longer writes) means the on-disk schema no
+        # longer matches the data being written. Deleting the database lets the
+        # next run rebuild a valid cache from scratch.
+        if delete_db_on_operational_error:
+            rm_db(conn)
+        return False, f'Integrity Error: {e}, Query: {sql}, Data: {data}'
     except Exception as e:
         return False, f'Query failed: {sql}, Error: {e}, Data: {data}'
 
@@ -1237,7 +1266,8 @@ def select(
       If `True`, return results as a list of dictionaries.
       If `False`, return raw SQLite row objects. Defaults to `True`.
     - **delete_db_on_operational_error** (`bool`, optional):
-      If `True`, deletes the database file when an `OperationalError` occurs.
+      If `True`, deletes the database file when the on-disk database turns out
+      to be unusable (e.g. a schema mismatch between releases).
       Defaults to `True`.
 
     ### Returns