improve tests

[lunny]

No description provided.

[codecov-io]

Codecov Report

Merging #1250 into master will increase coverage by 0.36%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #1250      +/-   ##
==========================================
+ Coverage   57.01%   57.38%   +0.36%     
==========================================
  Files          48       43       -5     
  Lines        8185     7807     -378     
==========================================
- Hits         4667     4480     -187     
+ Misses       2907     2772     -135     
+ Partials      611      555      -56

Impacted Files	Coverage Δ
logger.go	60.86% <0%> (-5.8%)	⬇️
rows.go	52.38% <0%> (-3.76%)	⬇️
dialect_sqlite3.go	77.29% <0%> (-2.44%)	⬇️
tag.go	77.09% <0%> (-2.36%)	⬇️
helpers.go	57.41% <0%> (-2.32%)	⬇️
dialect_mssql.go	74.01% <0%> (-1.39%)	⬇️
engine.go	61.53% <0%> (-1.31%)	⬇️
session_schema.go	59.12% <0%> (-1.2%)	⬇️
session_exist.go	62.26% <0%> (-0.7%)	⬇️
session_update.go	56.44% <0%> (-0.15%)	⬇️
... and 17 more

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