Troubleshooting File Geodatabase Issues In Qgis
Locating Corrupted Geodatabase Files
A corrupted file geodatabase can cause a variety of issues in QGIS, including crashes, missing data, and errors opening or editing data. Here are some tips for locating corrupted geodatabase files:
- Check the QGIS log file for error messages related to the geodatabase. Errors about corrupt files or inability to open tables can indicate corruption.
- Try opening the geodatabase in Esri’s ArcCatalog. If ArcCatalog cannot open it or reports errors, corruption is likely.
- In Windows Explorer, check the file size and date modified of the geodatabase file. Unexpected small file sizes or old modification dates can indicate corruption.
- Scan the geodatabase file for errors using the “Check Geometry” tool in QGIS. Review the output for feature classes with geometry errors.
- If the geodatabase is stored in a database like PostgreSQL/PostGIS, check for corruption using database admin tools like pg_dump checks.
Once a corrupted geodatabase is located, try repairing it with QGIS or Esri tools. If it cannot be repaired, revert to a known good backup copy.
Fixing “Schema Locked” Errors
“Schema Locked” errors occur when the schema of a PostGIS database cannot be modified, usually because an edit session has not been properly closed. Some steps to fix include:
- Make sure no other applications like QGIS or Esri ArcMap have an open connection to that database.
- In pgAdmin or other Postgres admin tool, close any pending transactions that could lock the schema using ROLLBACK.
- Check Postgres settings for statement_timeout and idle transaction parameters and increase as needed.
- Use Postgres admin tools to unlock the schema with command ALTER TABLE…FORCE ROW LEVEL SECURITY.
- As a last resort, restart the Postgres database service to reset all connections and locks.
Properly closing database connections in QGIS can help prevent “Schema Locked” errors…
Handling Invalid Geometry Problems
Invalid geometries in feature classes can prevent geodatabase operations like edits, exports, and syncs. Steps to handle include:
- In QGIS, use Check Validity tool to list feature classes and features with geometry issues.
- For large errors, delete invalid features or reconstruct geometries with editing.
- For small precision errors, use PostGIS ST_SnapToGrid() function to correct.
- Alter the feature class tolerance setting to accommodate slightly invalid geometries.
- Export problem layers to a new geodatabase to improve or filter geometries.
Setting proper snapping and topology rules when…
Repairing Feature Class Sync Errors
Schema differences between source and target data during geodatabase replication can cause sync errors. To resolve:
- Review and correct schema and geometry differences between participating feature classes using Compare tool.
- For field mismatches, add missing fields using schema editing tools in QGIS or ArcCatalog.
- For field type mismatches, cast values to match or change field type definition.
- Ensure proper spatial references and geometry types/rules.
- Rebuild indexes to improve join and spatial performance during sync.
Using consistent schemas and storage formats can prevent…
Debugging Slow Performance Issues
Complex analyses and long edit sessions involving large geodatabases can bog down performance. Tactics include:
- Add spatial and attribute indexes on large feature classes used in joins or filters.
- Partition large feature classes into multiple class by location or attributes.
- Simplify complex feature geometries to reduce processing overhead.
- Upgrade PostgreSQL/PostGIS configuration for more connections, memory, faster storage.
- Offload selective processing to other GIS servers using distributed geodatabases.
Optimizing data storage, database configuration, and…
Correcting Metadata Import Failures
Importing metadata records into a PostGIS geodatabase can sometimes fail with schema errors. To correct:
- Review PostGIS schema for necessary meta tables: meta_metadata, meta_general, meta_column, etc.
- Compare source metadata types to target database column types for mismatches.
- Adjust length, precision, etc of meta columns to fit incoming metadata.
- Temporarily relax NOT NULL constraints if needed to import records.
- Use PostGIS function AddGeometryColumn() to ensure geometry meta information.
Careful attention to metadata formats during PostGIS geodatabase design…
Unlocking Edits and Versions
Stalled edit sessions can lock features classes for editing. To release locks:
- In QGIS browser panel, review feature classes for locks indicated by edit icons.
- Using Version Manager, rollback any long transactions blocking access.
- Unlock layers using context menu or with SQL using UPDATE/DELETE versioning metadata tables.
- Commit or rollbackchanges from any disconnected QGIS instances with pending edits.
- As last resort, export locked data to new geodatabase to reset edit state .
Enabling multiuser editing environments and…
Recovering Deleted Feature Classes
Accidentally deleted feature classes can be recovered by:
- Checking QGIS browser panel trash folder for any recently deleted layers.
- Scanning geodatabase metadata tables for a dropped FEATURECLASS entry.
- Using PostGIS pg_dump to extract all tables to SQL text dump and searching CODE> for feature class SQL.
- Restoring previous backups of the geodatabase files or database.
- Using OS level file recovery tools to rescue deleted file directory entries.
Care should be taking when deleting feature classes as recovery options are limited. Using clearly named…
Contacting Esri Technical Support
If the above troubleshooting steps do not resolve file geodatabase issues, technical help is available from:
- Esri Support Website to search knowledge base articles, technical documents.
- Esri User Forums to post questions to community of practice.
- Esri Technical Support Help Desk to submit detailed technical issues for review by staff support team.
Be sure to provide detailed information on workflow steps, error messages, system and data specifics when requesting technical support for optimal response.