apache/shardingsphere · error · ColumnLabelNotFoundException

21

21

Error message

Can not find column label '%s'.

What it means

ColumnLabelNotFoundException (SQLState/error code 21 family) thrown by DatabaseMetaDataResultSet.findColumn when the requested column label is not a key in columnLabelIndexMap. This metadata ResultSet is backed by in-memory rows produced by ShardingSphere's DatabaseMetaData implementation, so only the exact labels it defines are resolvable.

Source

Thrown at jdbc/src/main/java/org/apache/shardingsphere/driver/jdbc/core/resultset/DatabaseMetaDataResultSet.java:378

    }
    
    @Override
    public Object getObject(final int columnIndex) throws SQLException {
        checkClosed();
        checkColumnIndex(columnIndex);
        return currentDatabaseMetaDataObject.getObject(columnIndex);
    }
    
    @Override
    public Object getObject(final String columnLabel) throws SQLException {
        return getObject(findColumn(columnLabel));
    }
    
    @Override
    public int findColumn(final String columnLabel) throws SQLException {
        checkClosed();
        if (!columnLabelIndexMap.containsKey(columnLabel)) {
            throw new ColumnLabelNotFoundException(columnLabel).toSQLException();
        }
        return columnLabelIndexMap.get(columnLabel);
    }
    
    @Override
    public int getType() throws SQLException {
        checkClosed();
        return type;
    }
    
    @Override
    public int getConcurrency() throws SQLException {
        checkClosed();
        return concurrency;
    }
    
    @Override
    public void setFetchDirection(final int direction) throws SQLException {

View on GitHub (pinned to e952770a21)

Solutions

1. Inspect the result set's metadata (ResultSetMetaData.getColumnLabel) at runtime and use the exact labels present.
2. Read columns by index instead of label for metadata result sets.
3. Check the JDBC/DatabaseMetaData spec for which columns the specific metadata method returns, and fix the label name.

Example fix

// before
rs = meta.getTables(null, null, "%", null);
String db = rs.getString("DATABASE_NAME"); // label not in getTables result
// after
String db = rs.getString("TABLE_CAT"); // spec-defined label

int idx = -1; try { idx = rs.findColumn("TABLE_NAME"); } catch (SQLException ok) { /* fall back by spec order */ }

catch (SQLException ex) { // ColumnLabelNotFoundException: enumerate available labels
 for (int i=1;i<=rs.getMetaData().getColumnCount();i++) log(rs.getMetaData().getColumnLabel(i)); }

When it happens

Trigger: Calling getString/findColumn(String) on a ResultSet returned by DatabaseMetaData methods (getTables, getColumns, getIndexInfo, ...) with a label that does not exist for that metadata result set — e.g. asking for 'TABLE_NAME' on a result set that does not expose it, or a case-sensitive mismatch.

Common situations: Framework/schema-tooling code assuming a specific metadata column exists across drivers; porting tools written for another DB's metadata layout; typos or wrong-case labels; reading the wrong metadata method's result set.

Related errors

• 2
• getHoldability
• Unsupported BLR version: %s
• Expected blr_begin
• Expected blr_message

AI-assisted analysis of apache/shardingsphere@e952770a21 (2026-08-14). Data as JSON: /api/errors/bbe634aefe9df2d6. Report an issue: GitHub.