What causes "Error querying schema: {}" in tursodatabase/turso?

Read the appended inner error text — it names the real cause (I/O, malformed image, locked, ...).

Error querying schema: {}

Error message

Error querying schema: {}

What it means

The generic failure branch of '.indexes' (display_indexes in cli/app.rs): any error other than the specific missing-sqlite_schema case that occurs while selecting index names from the schema is wrapped with 'Error querying schema: {err}', with the underlying engine error appended verbatim.

Source

Thrown at cli/app.rs:1638

                ),
                None => format!("SELECT name FROM {name}.sqlite_schema WHERE type='index' ORDER BY 1"),
            };
            let handler = |row: &turso_core::Row| {
                if let Ok(Value::Text(idx)) = row.get::<&Value>(0) {
                    if let Some(prefix) = prefix {
                        indexes.push_str(prefix);
                        indexes.push('.');
                    }
                    indexes.push_str(idx.as_str());
                    indexes.push(' ');
                }
                Ok(())
            };
            if let Err(err) = self.handle_row(&sql, handler) {
                if err.to_string().contains("no such table: sqlite_schema") {
                    return Err(anyhow::anyhow!("Unable to access database schema. The database may be using an older SQLite version or may not be properly initialized."));
                } else {
                    return Err(anyhow::anyhow!("Error querying schema: {}", err));
                }
            }
        }
        if !indexes.is_empty() {
            let _ = self.writeln(indexes.trim_end().as_bytes());
        }
        Ok(())
    }

    fn display_tables(&mut self, pattern: Option<&str>) -> anyhow::Result<()> {
        let mut tables = String::new();

        for name in self.database_names()? {
            let prefix = (name != "main").then_some(&name);
            let sql = match pattern {
                Some(pattern) => format!(
                    "SELECT name FROM {name}.sqlite_schema WHERE type in ('table', 'view') AND name NOT LIKE 'sqlite_%' AND name LIKE '{pattern}' ORDER BY 1"
                ),

View on GitHub (pinned to bad083fafb)

Solutions

Read the appended inner error text — it names the real cause (I/O, malformed image, locked, ...).
Run PRAGMA integrity_check; to test the file.
Run '.databases' to confirm which databases are actually attached before using a 'db.' prefix.
If the inner error mentions locking, close competing writers or retry after they finish.

Defensive patterns

Strategy: try-catch

Validate before calling

-- Pre-flight the objects your pattern references:
.databases               -- confirm the db prefix is attached
SELECT name FROM sqlite_schema WHERE type='index' AND name LIKE 'my%';

Try / catch

// Inspect the inner error: the wrapper only adds context, the cause is appended.
if let Err(e) = shell.run_dot_command(".indexes") {
    let msg = e.to_string();
    let inner = msg.strip_prefix("Error querying schema: ").unwrap_or(&msg);
    // branch on inner: io error vs malformed image vs unknown object
}

Prevention

Surface the appended inner error first — it is the real diagnosis.
Run PRAGMA integrity_check on any file that starts throwing unexpected schema errors.

When it happens

Trigger: Running '.indexes [pattern]' where the backing query fails for a non-schema-table reason: I/O error reading the file, a malformed database image, an unattached 'db.' prefix used in the pattern, or an internal engine error surfacing through handle_row.

Common situations: Database file deleted or permissions changed while the CLI session was open; corrupted page containing the schema b-tree; scripts that assume an ATTACH that never happened.

Related errors

AI-assisted analysis of tursodatabase/turso@bad083fafb (2026-08-16). Data as JSON: /api/errors/eecc390a1808e22d. Report an issue: GitHub.