Fix the wrong search result of the pgvector

[SimFG]

issue: #511

[sre-ci-robot]

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[codecov[bot]]

Codecov Report

Merging #514 (84e9a45) into dev (8f7d36a) will increase coverage by 0.00%. The diff coverage is 100.00%.

Additional details and impacted files

[](https://app.codecov.io/gh/zilliztech/GPTCache/pull/514?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=zilliztech) ```diff @@ Coverage Diff @@ ## dev #514 +/- ## ======================================= Coverage 94.05% 94.05% ======================================= Files 94 94 Lines 3919 3920 +1 ======================================= + Hits 3686 3687 +1 Misses 233 233 ``` | [Files Changed](https://app.codecov.io/gh/zilliztech/GPTCache/pull/514?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=zilliztech) | Coverage Δ | | |---|---|---| | [gptcache/\_\_init\_\_.py](https://app.codecov.io/gh/zilliztech/GPTCache/pull/514?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=zilliztech#diff-Z3B0Y2FjaGUvX19pbml0X18ucHk=) | `100.00% <100.00%> (ø)` | | | [gptcache/manager/vector\_data/pgvector.py](https://app.codecov.io/gh/zilliztech/GPTCache/pull/514?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=zilliztech#diff-Z3B0Y2FjaGUvbWFuYWdlci92ZWN0b3JfZGF0YS9wZ3ZlY3Rvci5weQ==) | `98.79% <100.00%> (+0.01%)` | :arrow_up: |