What causes "failed to generate index SDL for %s.%s" in bytebase/bytebase?

Re-run the SDL export to rule out a transient writer failure

failed to generate index SDL for %s.%s

Error message

failed to generate index SDL for %s.%s

What it means

This error wraps failures from writeIndexSDL while emitting the CREATE INDEX statement for a non-constraint index on a materialized view during multi-file SDL generation. As with the other SDL writers in this file, the sink is a strings.Builder whose writes cannot fail, so the wrap is defensive. If it fires, the message identifies the schema and index name whose SDL could not be generated.

Source

Thrown at backend/plugin/schema/pg/get_database_definition.go:4318

			// Write materialized view comment if present
			if len(materializedView.Comment) > 0 {
				buf.WriteString("\n")
				if err := writeMaterializedViewCommentSDL(&buf, schemaName, materializedView); err != nil {
					return nil, errors.Wrapf(err, "failed to generate materialized view comment for %s.%s", schemaName, materializedView.Name)
				}
			}

			// Write indexes on materialized view
			for _, index := range materializedView.Indexes {
				// Skip constraint-based indexes
				if index.Primary || index.IsConstraint {
					continue
				}

				buf.WriteString("\n")
				if err := writeIndexSDL(&buf, schemaName, materializedView.Name, index, false); err != nil {
					return nil, errors.Wrapf(err, "failed to generate index SDL for %s.%s", schemaName, index.Name)
				}
				buf.WriteString(";\n")

				// Write index comment if present
				if len(index.Comment) > 0 {
					buf.WriteString("\n")
					if err := writeIndexCommentSDL(&buf, schemaName, index); err != nil {
						return nil, errors.Wrapf(err, "failed to generate index comment for %s.%s", schemaName, index.Name)
					}
				}
			}

			files = append(files, schema.File{
				Name:    fmt.Sprintf("schemas/%s/materialized_views/%s.sql", schemaName, materializedView.Name),
				Content: buf.String(),
			})
		}

View on GitHub (pinned to 1870550677)

Solutions

Re-run the SDL export to rule out a transient writer failure
Check disk space / permissions on the output destination if SDL is streamed to disk
Unwrap the error to see the underlying writer failure
If seen after a code change, review writeIndexSDL for newly introduced I/O

Defensive patterns

Strategy: try-catch

Try / catch

files, err := GetMultiFileDatabaseDefinition(ctx, db, meta)
if err != nil {
    var wrapped error
    if errors.As(err, &wrapped) && strings.Contains(err.Error(), "failed to generate index SDL") {
        return fmt.Errorf("retry SDL export: %w", wrapped)
    }
    return err
}

Prevention

Avoid redirecting SDL generation to fallible I/O mid-run; buffer in memory and write once
Verify disk space/permissions before exporting
Retry the export on transient I/O errors
Report index names from the wrapped message when filing bugs

When it happens

Trigger: GetMultiFileDatabaseDefinition iterates materializedView.Indexes, skips primary/constraint indexes, and writeIndexSDL returns a non-nil error for a given index.

Common situations: Only realistically triggered by an injected/redirected failing writer (disk full, closed pipe) or future refactor of writeIndexSDL to a real I/O sink; not by any property of the index metadata itself.

Understand the failure class

Background: "failed to write file", "Could not save figure", "Error saving remote file" — file write failed: causes and fixes across languages and libraries — this error's family across 38 libraries.

Related errors

AI-assisted analysis of bytebase/bytebase@1870550677 (2026-09-06). Data as JSON: /api/errors/05ad85b789047421. Report an issue: GitHub.