[Bug] The CAST operator has a logical error causing precision loss when converting floating-point values.
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- Java
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描述
### Search before asking
- [X] I searched in the [issues](https://github.com/apache/iotdb/issues) and found nothing similar.
### Version
version 1.3.3 (Build: ad95a7e)
### Describe the bug and provide the minimal reproduce step
```
DROP DATABASE root.db0
CREATE DATABASE root.db0
CREATE TIMESERIES root.db0.t1 WITH datatype=FLOAT compressor=GZIP 'MAX_POINT_NUMBER'='6';
INSERT INTO root.db0(timestamp, t1) VALUES (1643027794590, 0.5522);
INSERT INTO root.db0(timestamp, t1) VALUES (1643027794600, 0.8044);
# query 1
select t1 from root.db0 where t1 <= 0.8044
# query 2
select t1 from root.db0 where cast(t1 as float) <= 0.8044
```
### What did you expect to see?
Query 1 returned result set: 0.5522 and 0.8044
Query 2 returned result set: 0.5522 and 0.8044
### What did you see instead?
Query 1 returned result set: 0.5522 and 0.8044
Query 2 returned result set: 0.5522
### Anything else?
Dear IoTDB team, When using the CAST operator to convert a FLOAT value to FLOAT, the value theoretically should remain unchanged. However, the above test case indicates that a logical error causing precision loss occurs after the CAST conversion.
### Are you willing to submit a PR?
- [ ] I'm willing to submit a PR!
贡献指南
调研方向
针对 IoTDB 1.3.3 运行 issue 中的 SQL 复现,并比较两个查询结果。跟踪 CAST 表达式处理和 FLOAT 比较路径,然后验证将 FLOAT 转换为 FLOAT 会保留该值,并且会返回预期的两行。
由索引模型根据 Issue 内容生成。
评估
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- java
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- databases
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- 4/5
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- 3-5 天
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- 45/100