我正在收集twitter流,并将它存储在sqlite db.Since中,流正在到来,数据库越来越大,我执行了一个命令来删除比minute.But更老的tweet,这里只有tweet,而且数据库正在获得bigger.Please帮助,因为我对sqlite还不熟悉。class listener(StreamListener):
try: tweet = unidecode(data['text'])
text = p
org.springframework.transaction.TransactionSystemException: Could not roll back JDBC transaction; nested exception is com.mysql.jdbc.exceptions.jdbc4java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)这似乎与应用程序正在进行的mysql</
我试图将两个查询合并在一起,但不确定方法。我对加入和如何工作知之甚少。用户:email, 余额:userNumber, debit (multiple entries in which I use SUM - SUM group by userNumber)SELECT SUM(credit) - SUM(debit) as 'balance' FROM balances GROUP BY userNumber
SELECT u.i