Introduce field mapper

[vjik]

Q	A
Is bugfix?	❌
New feature?	✔️
Breaks BC?	✔️

[codecov]

Codecov Report

❌ Patch coverage is 84.74576% with 9 lines in your changes missing coverage. Please review.
✅ Project coverage is 76.61%. Comparing base (d1d7ef3) to head (a353320).
⚠️ Report is 1 commits behind head on master.

Files with missing lines	Patch %	Lines
src/FilterHandler/EqualsExpressionHandler.php	0.00%	4 Missing ⚠️
src/QueryDataReader.php	89.18%	4 Missing ⚠️
src/FilterHandler.php	66.66%	1 Missing ⚠️

❗ There is a different number of reports uploaded between BASE (d1d7ef3) and HEAD (a353320). Click for more details.

HEAD has 1 upload less than BASE

Flag	BASE (d1d7ef3)	HEAD (a353320)
	6	5

Additional details and impacted files

@@              Coverage Diff               @@
##              master     #110       +/-   ##
==============================================
- Coverage     100.00%   76.61%   -23.39%     
- Complexity        90       98        +8     
==============================================
  Files             21       22        +1     
  Lines            271      295       +24     
==============================================
- Hits             271      226       -45     
- Misses             0       69       +69     

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[samdark]

👍 Need docs.

[Tigrov]

Should it return new ColumnName() if the value is string?

[vjik]

I think, no. Yii DB quote string values