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PSQLException: current transaction is aborted, commands ignored until end of transaction block

由 蹲街弑〆低调 提交于 2019-11-28 03:10:19
Eric Leschinski

I got this error using Java and postgresql doing an insert on a table. I will illustrate how you can reproduce this error:

org.postgresql.util.PSQLException: ERROR: 
current transaction is aborted, commands ignored until end of transaction block

Summary:

The reason you get this error is because you have entered a transaction and one of your SQL Queries failed, and you gobbled up that failure and ignored it. But that wasn't enough, THEN you used that same connection, using the SAME TRANSACTION to run another query. The exception gets thrown on the second, correctly formed query because you are using a broken transaction to do additional work. Postgresql by default stops you from doing this.

I'm using: PostgreSQL 9.1.6 on x86_64-redhat-linux-gnu, compiled by gcc (GCC) 4.7.2 20120921 (Red Hat 4.7.2-2), 64-bit".

My postgresql driver is: postgresql-9.2-1000.jdbc4.jar

Using java version: Java 1.7

Here is the table create statement to illustrate the Exception:

CREATE TABLE moobar
(
    myval   INT
);

Java program causes the error:

public void postgresql_insert()
{
    try  
    {
        connection.setAutoCommit(false);  //start of transaction.

        Statement statement = connection.createStatement();

        System.out.println("start doing statement.execute");

        statement.execute(
                "insert into moobar values(" +
                "'this sql statement fails, and it " +
                "is gobbled up by the catch, okfine'); ");

        //The above line throws an exception because we try to cram
        //A string into an Int.  I Expect this, what happens is we gobble 
        //the Exception and ignore it like nothing is wrong.
        //But remember, we are in a TRANSACTION!  so keep reading.

        System.out.println("statement.execute done");

        statement.close();

    }
    catch (SQLException sqle)
    {
        System.out.println("keep on truckin, keep using " +
                "the last connection because what could go wrong?");
    }

    try{
        Statement statement = connection.createStatement();

        statement.executeQuery("select * from moobar");

        //This SQL is correctly formed, yet it throws the 
        //'transaction is aborted' SQL Exception, why?  Because:
        //A.  you were in a transaction.
        //B.  You ran a sql statement that failed.
        //C.  You didn't do a rollback or commit on the affected connection.

    }
    catch (SQLException sqle)
    {
        sqle.printStackTrace();
    }   

}

The above code produces this output for me:

start doing statement.execute

keep on truckin, keep using the last connection because what could go wrong?

org.postgresql.util.PSQLException: 
  ERROR: current transaction is aborted, commands ignored until 
  end of transaction block

Workarounds:

You have a few options:

  1. Simplest solution: Don't be in a transaction. Set the connection.setAutoCommit(false); to connection.setAutoCommit(true);. It works because then the failed SQL is just ignored as a failed sql statement. You are welcome to fail sql statements all you want and postgresql won't stop you.

  2. Stay being in a transaction, but when you detect that the first sql has failed, either rollback/re-start or commit/restart the transaction. Then you can continue failing as many sql queries on that database connection as you want.

  3. Don't catch and ignore the Exception that is thrown when a sql statement fails. Then the program will stop on the malformed query.

  4. Get Oracle instead, Oracle doesn't throw an exception when you fail a query on a connection within a transaction and continue using that connection.

In defense of postgresql's decision to do things this way... Oracle was making you soft in the middle letting you do dumb stuff and overlooking it.

vyegorov

Check the output before the statement that caused current transaction is aborted. This typically means that database threw an exception that your code had ignored and now expecting next queries to return some data.

So you now have a state mismatch between your application, which considers things are fine, and database, that requires you to rollback and re-start your transaction from the beginning.

You should catch all exceptions and rollback transactions in such cases.

Here's a similar issue.

I think that the best solution is use java.sql.Savepoint.

Before execute query which can throw SQLException use method Connection.setSavepoint() and if exception will be throw you only rollback to this savepoint not rollback all transaction.

Example code:

Connection conn = null;
Savepoint savepoint = null;
try {
    conn = getConnection();
    savepoint = conn.setSavepoint();
    //execute some query
} catch(SQLException e) {
    if(conn != null && savepoint != null) {
        conn.rollback(savepoint);
    }
} finally {
   if(conn != null) {
      try {
          conn.close();
      } catch(SQLException e) {}

   }
}

In Ruby on Rails PG, I had created a migration, migrated my DB, but forgot to restart my development server. I restarted my server and it worked.

The reason for this error is that there are other database before the wrong operation led to the current database operation can not be carried out（i use google translation to translate my chinese to english）

There's been some work done on the postgresql JDBC Driver, related to this behaviour:
see https://github.com/pgjdbc/pgjdbc/pull/477

It is now possible, by setting 

autosave=always
in the connection (see https://jdbc.postgresql.org/documentation/head/connect.html) to avoid the 'current transaction is aborted' syndroma.
Overhead due to handling a savepoint around the statement execution is kept very low (see link above for details).

The issue has been fixed in Infinispan 5.1.5.CR1: ISPN-2023

You need to rollback. The JDBC Postgres driver is pretty bad. But if you want to keep your transaction, and just rollback that error, you can use savepoints:

try {
_stmt = connection.createStatement();
_savePoint = connection.setSavepoint("sp01");
_result = _stmt.executeUpdate(sentence) > 0;
} catch (Exception e){
 if (_savePoint!=null){
 connection.rollback(_savePoint);
}
}

Read more here:

http://www.postgresql.org/docs/8.1/static/sql-savepoint.html

I had the same issue but then realised there is a table with the same name in the database. After deleting that I was able to import the file.

This is very weird behavior of PostgreSQL, it is even not " in-line with the PostgreSQL philosophy of forcing the user to make everything explicit" - as the exception was caught and ignored explicitly. So even this defense does not hold. Oracle in this case behaves much more user-friendly and (as for me) correctly - it leaves a choice to the developer.

This can happen if you are out of disk space on the volume.

virtualpathum

I just encounter the same error. I was able to figure out the root cause by enabling the log_statement and log_min_error_statement in my local PostgreSQL.

I Referred this

I am using JDBI with Postgres, and encountered the same problem, i.e. after a violation of some constraint from a statement of previous transaction, subsequent statements would fail (but after I wait for a while, say 20-30 seconds, the problem goes away).

After some research, I found the problem was I was doing transaction "manually" in my JDBI, i.e. I surrounded my statements with BEGIN;...COMMIT; and it turns out to be the culprit!

In JDBI v2, I can just add @Transaction annotation, and the statements within @SqlQuery or @SqlUpdate will be executed as a transaction, and the above mentioned problem doesn't happen any more!

Set conn.setAutoCommit(false) to conn.setAutoCommit(true)

Commit the transactions before initiating a new one.

Change the isolation level from repeatable read to read committed.

标签
postgresql
jboss
infinispan
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