[Solved] what is the most performance way to remove duplicate data of PostgreSQL 13

How to optimize this SQL query?

In case you have your own slow SQL query, you can optimize it automatically here.

For the query above, the following recommendations will be helpful as part of the SQL tuning process.
You'll find 3 sections below:

  1. Description of the steps you can take to speed up the query.
  2. The optimal indexes for this query, which you can copy and create in your database.
  3. An automatically re-written query you can copy and execute in your database.
The optimization process and recommendations:
  1. Create Optimal Indexes (modified query below): The recommended indexes are an integral part of this optimization effort and should be created before testing the execution duration of the optimized query.
Optimal indexes for this query:
CREATE INDEX sentence_idx_ctid ON "sentence" ("ctid");
CREATE INDEX sentence_idx_sentence_zh_ctid ON "sentence" ("sentence_zh","ctid");
The optimized query:
SELECT
        1 
    FROM
        sentence 
    WHERE
        sentence.ctid NOT IN (
            SELECT
                min(sentence.ctid) 
            FROM
                sentence 
            GROUP BY
                sentence.sentence_zh
        )

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