修复oracle 查询中带clog 列 不能正常查询的bug

[yzypals]

修复oracle 查询中带clog 列 不能正常查询的bug

[codecov]

Codecov Report

Merging #250 into master will decrease coverage by 0.02%.
The diff coverage is 57.14%.

@@            Coverage Diff             @@
##           master     #250      +/-   ##
==========================================
- Coverage   83.16%   83.14%   -0.03%     
==========================================
  Files          65       65              
  Lines        8134     8138       +4     
==========================================
+ Hits         6765     6766       +1     
- Misses       1369     1372       +3

Impacted Files	Coverage Δ
sql/engines/oracle.py	95.31% <57.14%> (-1.5%)	⬇️

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