批处理-使用Hibernate/Spring数据插入Postgres DB : 60K行需要2分钟，这是不可接受的

Question

我需要使用Hibernate/Spring数据将60K行插入到Java/Spring应用程序中的Postgres中。

插入的数据是(1) USERS_T，(2)相关的新用户也必须在STUDY_PARTICIPANTS_T中。

下面的内容正在工作，但性能很差：60K需要2分钟。注意到，我正在填写Hibernate实体，然后根据1000大小的列表执行saveAll。

        UsersT user = new UsersT();
        user.setUsername(study.getAbbreviation().toUpperCase()+subjectId);
        user.setRoleTypeId(new LookupT(150));
        user.setCreatedDate(new Date());
        //...
        List<StudyParticipantsT> participants = new ArrayList<StudyParticipantsT>();
        StudyParticipantsT sp = new StudyParticipantsT();
        sp.setStudyT(study);
        sp.setUsersT(user);
        sp.setSubjectId(subjectId);
        sp.setLocked("N");
        participants.add(sp);
        user.setStudyParticipantsTs(participants);

        // Add to Batch-Insert List; if list size ready for batch-insert, or if at the end of all subjectIds, do Batch-Insert saveAll() and clear the list
        batchInsertUsers.add(user);
        if (batchInsertUsers.size() == 1000 || i == subjectIds.size() - 1) {
            // Log this Batch-Insert
            if(log.isDebugEnabled()){
                log.debug("createParticipantsAccounts() Batch-Insert: Saving " + batchInsertUsers.size() + " records");
            }
            userDAO.saveAll(batchInsertUsers);
            // Reset list
            batchInsertUsers.clear();
        }          

我找到了一个线程，其中有人遇到了同样的问题，他们找到的唯一解决方案是为1000的每个块组合一个自定义的本机-SQL INSERT (..), (..), (..)字符串，然后手动运行，完全删除ORM/Hibernate层：Need to insert 100000 rows in mysql using hibernate in under 5 seconds。

但我的插入涉及到一些连接的表。我可以自己花时间将所有这些实体语句重写为自定义SQL，但这并不简单。

还有其他解决办法吗？我正在使用-Spring5.0.2- Hibernate5.2.12

Answer 1

我们使用SpringJDBC的jdbcTemplate.batchUpdate (无Hibernate)并预先为任何外键保留一个序列范围，从而提高了性能。

我们没有深入到实际的N个重复的INSERT语句的级别，上面提到的其他海报也这样做了；我们仍然在使用框架方法(JDBCTemplate)，但至少我们不再使用Hibernate/ORM了。这个方法是快速的，但是它没有N个重复的INSERTs那么快，但是现在它是可以接受的。

实际的SpringJDBC批处理--插入是通过jdbcTemplate.batchUpdate(sqlInsert, new BatchPreparedStatementSetter() {..}进行的，我们实际上是自己分批-- BatchPreparedStatementSetter不会自动为我们拆分任何东西，它只会提交具有预定大小的特定批处理。

/**
 * The following method performs a Native-SQL Batch-Insert of Participant accounts (using JdbcTemplate) to improve performance.
 * Each Participant account requires 2 INSERTs: (1) USERS_T, (2) STUDY_PARTICIPANTS_T (with an FK reference to USERS_T.ID).
 * Since there is no easy way to track the Sequence IDs between the two Batch-Inserts, we reserve the ID range for both tables, and 
 * then manually calculate our own IDs for USERS_T and STUDY_PARTICIPANTS_T ourselves.
 * Initially, domain objects are filled out; then they are added to the Batch List that we submit and clear ourselves.
 * (Originally the Batch-Insert was implemented with Hibernate/HQL, but due to slow performance it was nativized with jdbcTemplate.)
 * 
 * NOTE: The entire method is @Transactional and all data will be rolled back in case of any exceptions in this method (rollbackFor=Exception.class).
 * The updated Sequence values (set during reservation) will not be rolled back in this case, but Sequence gaps are normal. 
 */
@Override
@Transactional(readOnly = false, rollbackFor = Exception.class)
public void createParticipantsAccounts(long studyId, List<String> subjectIds) throws Exception {

    int maxInsertParticipantsBatchSize = 1000; // Batch size is 1000
    
    /*
      We need to insert into 2 tables, USERS_T and STUDY_PARTICIPANTS_T. 
      The table STUDY_PARTICIPANTS_T has an FK dependency on USERS_T.ID.
      Since there is no easy way to track the Sequence IDs between the two Batch-Inserts, we reserve the ID range for both tables, 
      and then manually calculate our own IDs for USERS_T and STUDY_PARTICIPANTS_T ourselves.
      The Sequences are immediately updated to the calculated final values to reserve the range. 
     */
    // 1. Obtain current Sequence values
    Integer currUsersTSeqVal = userDAO.getCurrentUsersTSeqVal();
    Integer currStudyParticipantsTSeqVal = studyParticipantsDAO.getCurrentStudyParticipantsTSeqVal();
    // 2. Immediately update the Sequences to the calculated final value (this reserves the ID range immediately)
    // In Postgres, updating the Sequences is: SELECT setval('users_t_id_seq', :val)
    userDAO.setCurrentUsersTSeqVal(currUsersTSeqVal + subjectIds.size());
    studyParticipantsDAO.setCurrentStudyParticipantsTSeqVal(currStudyParticipantsTSeqVal + subjectIds.size());                          
    
    // List for Batch-Inserts, maintained and submitted by ourselves in accordance with our batch size
    List<UsersT> batchInsertUsers = new ArrayList<UsersT>();        
    
    for(int i = 0; i < subjectIds.size(); i++) {
        
        String subjectId = subjectIds.get(i);           
        
        // Prepare domain object (UsersT with associated StudyParticipantsT) to be used in the Native-SQL jdbcTemplate batchUpdate
        UsersT user = new UsersT();
        user.setId(currUsersTSeqVal + 1 + i); // Set ID to calculated value
        user.setUsername(study.getAbbreviation().toUpperCase()+subjectId);
        user.setActiveFlag(true);
        // etc., fill out object, then subobject:
        List<StudyParticipantsT> participants = new ArrayList<StudyParticipantsT>();
        StudyParticipantsT sp = new StudyParticipantsT();
        sp.setId(currStudyParticipantsTSeqVal + 1 + i); // Set ID to caculated value
        // ...etc.
        user.setStudyParticipantsTs(participants);
        
        // Add to Batch-Insert List of Users
        batchInsertUsers.add(user);
        
        // If list size ready for Batch-Insert, or if at the end of all subjectIds, perform Batch Insert (both tables) and clear list
        if (batchInsertUsers.size() == maxInsertParticipantsBatchSize || i == subjectIds.size() - 1) {
            
            // Part 1: Insert batch into USERS_T
            nativeBatchInsertUsers(jdbcTemplate, batchInsertUsers);             
            // Part 2: Insert batch into STUDY_PARTICIPANTS_T
            nativeBatchInsertStudyParticipants(jdbcTemplate, batchInsertUsers);             
            // Reset list
            batchInsertUsers.clear();
        }
    }
}

实际批处理的子方法-插入：

/**
 * Native-SQL Batch-Insert into USERS_T for Participant Upload.
 * NOTE: This method is part of its Parent's @Transactional. (Note also that we need "final" on the List param for Inner-Class access to this variable.)
 *  
 * @param jdbcTemplate
 * @param batchInsertUsers
 */
private void nativeBatchInsertUsers(JdbcTemplate jdbcTemplate, final List<UsersT> batchInsertUsers) {

    String sqlInsert =  "INSERT INTO PUBLIC.USERS_T (id, password, user_name, created_by, created_date, last_changed_by, last_changed_date, " + 
                                                    "first_name, last_name, organization, phone, lockout_date, lockout_counter, last_login_date, " + 
                                                    "password_last_changed_date, temporary_password, active_flag, uuid, " + 
                                                    "role_type_id, ws_account_researcher_id) " +
                        "VALUES (?, ?, ?, ?, ?, ?, ?, " +
                                "?, ?, ?, ?, ?, ?, ?, " + 
                                "?, ?, ?, ?, " + 
                                "?, ?" +
                                ") ";

    
    jdbcTemplate.batchUpdate(sqlInsert, new BatchPreparedStatementSetter() {

        @Override
        public int getBatchSize() {
            return batchInsertUsers.size();
        }

        @Override
        public void setValues(PreparedStatement ps, int i) throws SQLException {
            ps.setInt(1, batchInsertUsers.get(i).getId()); // ID (provided by ourselves)
            // etc., set PS for each i-th object

        }       
        
    });
    
}

/**
 * Native-SQL Batch-Insert into STUDY_PARTICIPANTS_T for Participant Upload.
 * NOTE: This method is part of its Parent's @Transactional. (Note also that we need "final" on the List param for Inner-Class access to this variable.)
 *  
 * @param jdbcTemplate
 * @param batchInsertUsers
 */ 
private void nativeBatchInsertStudyParticipants(JdbcTemplate jdbcTemplate, final List<UsersT> batchInsertUsers) {
    
    String sqlInsert =  "INSERT INTO PUBLIC.STUDY_PARTICIPANTS_T (id, study_id, subject_id, user_id, locked, " +                                                                     "created_by, created_date, last_changed_by, last_changed_date) " + 
                        "VALUES (?, ?, ?, ?, ?, " +
                                "?, ?, ?, ? " +
                                ") ";
            
    jdbcTemplate.batchUpdate(sqlInsert, new BatchPreparedStatementSetter() {

        @Override
        public int getBatchSize() {
            return batchInsertUsers.size();
        }   
        
        @Override
        public void setValues(PreparedStatement ps, int i) throws SQLException {            
            
            ps.setInt(1, batchInsertUsers.get(i).getStudyParticipantsTs().get(0).getId()); // ID (provided by ourselves)
            // etc. 
        }
        
    });
    
}