Add fieldName in index

[wayblink]

/kind improvement

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[codecov]

Codecov Report

Merging #570 (1672c51) into master (18efb15) will increase coverage by 7.37%.
The diff coverage is 90.47%.

❗ Current head 1672c51 differs from pull request most recent head 8f26de9. Consider uploading reports for the commit 8f26de9 to get more accurate results

@@            Coverage Diff             @@
##           master     #570      +/-   ##
==========================================
+ Coverage   75.19%   82.57%   +7.37%     
==========================================
  Files          41       40       -1     
  Lines        4056     3672     -384     
==========================================
- Hits         3050     3032      -18     
+ Misses        893      526     -367     
- Partials      113      114       +1     

Files	Coverage Δ
client/collection.go	88.58% <100.00%> (ø)
client/index.go	78.29% <100.00%> (+0.69%)	⬆️
entity/indexes_search_param_gen.go	98.34% <ø> (ø)
entity/index.go	95.45% <75.00%> (-4.55%)	⬇️
entity/indexes_gen.go	94.68% <90.71%> (-4.58%)	⬇️

... and 8 files with indirect coverage changes