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session, com_stmt: store and restore the params for cursor fetch (#41441) #42239

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This is an automated cherry-pick of #41441

What problem does this PR solve?

Issue Number: close #40094

Problem Summary:

TiDB cannot handle concurrently running statements. This PR stores and restores the params.

What is changed and how it works?

Store and restore the prepared params in session

Check List

Tests

  • Unit test
  • Integration test
  • Manual test (add detailed scripts or steps below)
  • No code

The following JDBC codes run without panic:

import java.sql.*;

public class Example {
    public static void main(String[] args) throws SQLException, InterruptedException {
        Connection conn = DriverManager.getConnection("jdbc:mysql://127.0.0.1:4000/test?useCursorFetch=true&useServerPrepStmts=true&useSSL=false", "root", "");

        conn.setAutoCommit(false); // must set

        conn.prepareStatement("drop table if exists t").execute();
        conn.prepareStatement("create table t (id int auto_increment primary key, id_2 int)").execute();
        conn.prepareStatement("insert into t values (1,1)").execute();
        conn.prepareStatement("insert into t values (2,2)").execute();

        // submit a statement with more arguments:
        PreparedStatement statement1 = conn.prepareStatement("" +
                "select * " +
                "from " +
                "t " +
                "where id = ? and id_2 = ?");
        statement1.setFetchSize(500);
        statement1.setInt(1, 1);
        statement1.setInt(2, 2);
        ResultSet rs_1 = statement1.executeQuery();

        // submit a statement with less arguments:
        PreparedStatement statement2 = conn.prepareStatement("" +
                "select * " +
                "from " +
                "t " +
                "where (id = ?)");
        statement2.setFetchSize(500);
        statement2.setInt(1, 1);
        ResultSet rs_2 = statement2.executeQuery();

        // fetch the result from the first argument
        while (rs_1.next()) {
            int result = rs_1.getInt(1);

            System.out.println(result);
        }
        while (rs_2.next()) {
            int result = rs_2.getInt(1);

            System.out.println(result);
        }

        statement1.close();
        statement2.close();
        conn.commit();
        conn.close();

    }
}

Release note

Fix the issue that the prepared params are lost while executing another statement between EXECUTE and FETCH command.

Signed-off-by: ti-chi-bot <ti-community-prow-bot@tidb.io>
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@ti-chi-bot ti-chi-bot added do-not-merge/cherry-pick-not-approved release-note Denotes a PR that will be considered when it comes time to generate release notes. size/M Denotes a PR that changes 30-99 lines, ignoring generated files. type/cherry-pick-for-release-5.4 This PR is cherry-picked to release-5.4 from a source PR. size/XL Denotes a PR that changes 500-999 lines, ignoring generated files. and removed size/M Denotes a PR that changes 30-99 lines, ignoring generated files. labels Mar 15, 2023
@VelocityLight VelocityLight added cherry-pick-approved Cherry pick PR approved by release team. and removed do-not-merge/cherry-pick-not-approved labels Mar 28, 2023
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cherry-pick-approved Cherry pick PR approved by release team. release-note Denotes a PR that will be considered when it comes time to generate release notes. size/XL Denotes a PR that changes 500-999 lines, ignoring generated files. type/cherry-pick-for-release-5.4 This PR is cherry-picked to release-5.4 from a source PR.
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