In version 3.3.4.8 of TDengine, There is a logical error in converting a CAST BINARY compound expression to a DOUBLE value.

[LingweiKuang]

Bug Description

The abstract expression sequence is: CAST(timeseries AS BINARY(50)) != timeseries;

To Reproduce

Assume that we execute the following statement under a database named testdb.

DROP TABLE IF EXISTS t1;
CREATE TABLE t1(time TIMESTAMP, c0 DOUBLE);
INSERT INTO t1(time, c0) VALUES (1641024000000, 0.018518518518519), (1641024005000, 0.015151515151515), (1641024010000, 0.1234567891012345);

# query 1
SELECT c0, CAST(c0 AS BINARY(50)) FROM t1 WHERE CAST(c0 AS BINARY(50)) != c0;

Expected Behavior

Expected result set for Query 1: empty set

Actual behaviour

Query 1 returned result set: 0.018518518518519 and 0.015151515151515

Environment

• OS：Ubuntu Server 22.04 LTS 64bit
• TDengine Version：3.3.4.8

Additional Context

Hello, TDengine team. In the above query, I have encountered an issue while converting a DOUBLE value to BINARY, 0.1234567891012345 is correctly not retrieved; however, a value with lower precision, such as 0.015151515151515, is unexpectedly retrieved. The result of the cast does not meet expectations, This might be a logical error. Thank you.

[LingweiKuang]