googleapis/mcp-toolbox · error

unable to execute query: %w

Error message

unable to execute query: %w

What it means

RunSQL executes the statement through the pool with QueryContext (MindsDB supports MySQL prepared statements natively). Any driver- or server-level failure during execution is wrapped as "unable to execute query". This covers syntax errors, unknown tables/models, permission failures, and context cancellations.

Source

Thrown at internal/sources/mindsdb/mindsdb.go:114

}

func (s *Source) ToConfig() sources.SourceConfig {
	return s.Config
}

func (s *Source) MindsDBPool() *sql.DB {
	return s.Pool
}

func (s *Source) MySQLPool() *sql.DB {
	return s.Pool
}

func (s *Source) RunSQL(ctx context.Context, statement string, params []any) (any, error) {
	// MindsDB now supports MySQL prepared statements natively
	results, err := s.MindsDBPool().QueryContext(ctx, statement, params...)
	if err != nil {
		return nil, fmt.Errorf("unable to execute query: %w", err)
	}

	cols, err := results.Columns()
	if err != nil {
		return nil, fmt.Errorf("unable to retrieve rows column name: %w", err)
	}

	// create an array of values for each column, which can be re-used to scan each row
	rawValues := make([]any, len(cols))
	values := make([]any, len(cols))
	for i := range rawValues {
		values[i] = &rawValues[i]
	}
	defer results.Close()

	colTypes, err := results.ColumnTypes()
	if err != nil {
		return nil, fmt.Errorf("unable to get column types: %w", err)

View on GitHub (pinned to 8cc6e09de2)

Solutions

1. Check the wrapped driver error text for the underlying MySQL/MindsDB error code and message
2. Validate the statement in a MindsDB SQL client before wiring it into the tool config
3. Match the number of ? placeholders with the params slice length
4. Increase query timeout if long-running MindsDB predictions hit the context deadline

Example fix

// before
params: ["model_a"]
statement: "SELECT * FROM mindsdb.??"  # placeholder mismatch
// after
statement: "SELECT * FROM mindsdb.model_a"
params: []

var exists int
err := pool.QueryRowContext(ctx, "SHOW TABLES IN mindsdb LIKE ?", modelName).Scan(&exists)
_ = exists // validate model/table existence before running queries against it

results, err := pool.QueryContext(ctx, statement, params...)
if err != nil {
    var mysqlErr *mysql.MySQLError
    if errors.As(err, &mysqlErr) {
        switch mysqlErr.Number {
        case 1146: // unknown table/model
        case 1064: // syntax error
        }
    }
    if errors.Is(err, context.DeadlineExceeded) { /* raise timeout */ }
    return err
}

When it happens

Trigger: s.MindsDBPool().QueryContext(ctx, statement, params...) returns a non-nil error: SQL syntax error, unknown MindsDB model/table, parameter count mismatch, or ctx cancelled/timed out mid-query.

Common situations: Queries referencing a MindsDB model or database that doesn't exist; wrong number of ? placeholders vs params; long-running predictions hitting the query timeout; SQL that MySQL grammar rejects.

Related errors

• unable to execute query: %w
• unable to execute query: %w
• unable to execute query: %w
• unable to execute query: %w
• unable to create pool: %w

AI-assisted analysis of googleapis/mcp-toolbox@8cc6e09de2 (2026-09-05). Data as JSON: /api/errors/f1560e8bb868c5e0. Report an issue: GitHub.