public final ConstantContext constant() throws RecognitionException {
		ConstantContext _localctx = new ConstantContext(_ctx, getState());
		enterRule(_localctx, 154, RULE_constant);
		try {
			int _alt;
			setState(1612);
			_errHandler.sync(this);
			switch ( getInterpreter().adaptivePredict(_input,217,_ctx) ) {
			case 1:
				_localctx = new NullLiteralContext(_localctx);
				enterOuterAlt(_localctx, 1);
				{
				setState(1600);
				match(NULL);
				}
				break;
			case 2:
				_localctx = new IntervalLiteralContext(_localctx);
				enterOuterAlt(_localctx, 2);
				{
				setState(1601);
				interval();
				}
				break;
			case 3:
				_localctx = new TypeConstructorContext(_localctx);
				enterOuterAlt(_localctx, 3);
				{
				setState(1602);
				identifier();
				setState(1603);
				match(STRING);
				}
				break;
			case 4:
				_localctx = new NumericLiteralContext(_localctx);
				enterOuterAlt(_localctx, 4);
				{
				setState(1605);
				number();
				}
				break;
			case 5:
				_localctx = new BooleanLiteralContext(_localctx);
				enterOuterAlt(_localctx, 5);
				{
				setState(1606);
				booleanValue();
				}
				break;
			case 6:
				_localctx = new StringLiteralContext(_localctx);
				enterOuterAlt(_localctx, 6);
				{
				setState(1608); 
				_errHandler.sync(this);
				_alt = 1;
				do {
					switch (_alt) {
					case 1:
						{
						{
						setState(1607);
						match(STRING);
						}
						}
						break;
					default:
						throw new NoViableAltException(this);
					}
					setState(1610); 
					_errHandler.sync(this);
					_alt = getInterpreter().adaptivePredict(_input,216,_ctx);
				} while ( _alt!=2 && _alt!=org.antlr.v4.runtime.atn.ATN.INVALID_ALT_NUMBER );
				}
				break;
			}
		}
		catch (RecognitionException re) {
			_localctx.exception = re;
			_errHandler.reportError(this, re);
			_errHandler.recover(this, re);
		}
		finally {
			exitRule();
		}
		return _localctx;
	}
When true, the behavior of keywords follows ANSI SQL standard.
amoro-format-mixed/amoro-mixed-spark/v3.3/amoro-mixed-spark-3.3/src/main/gen-antlr/org/apache/amoro/spark/sql/parser/MixedFormatSqlExtendParser.java