Reputation: 8965
I have two methods below for checking if a match is in the database and if not if would call the insert method. My program has to go through thousands of rows and it takes a very long time. Am I doing this incorrectly? Anything I can do to significantly make this faster?
public Boolean isMatchIdInDatabase(String matchId) throws SQLException
{
Connection conn = null;
PreparedStatement pst = null;
ResultSet rs = null;
Boolean exists = false;
try
{
Class.forName("org.postgresql.Driver");
conn = DriverManager.getConnection(url, props);
pst = conn.prepareStatement("SELECT COUNT(*) FROM match where match_id = ?");
pst.setString(1, matchId);
rs = pst.executeQuery();
while (rs.next())
{
exists = rs.getBoolean(1);
}
}
catch (Exception e)
{
e.printStackTrace();
}
finally
{
pst.close();
rs.close();
conn.close();
}
return exists;
}
public Boolean insertMatchId(String matchId, String name, Timestamp birthdate, String bio, String accountId) throws SQLException, ClassNotFoundException
{
Connection conn = null;
PreparedStatement pst = null;
Boolean exists = false;
try
{
Class.forName("org.postgresql.Driver");
conn = DriverManager.getConnection(url, props);
pst = conn.prepareStatement("INSERT INTO match (match_id, name, birthdate, bio, account_id) values(?, ? , ?, ?, ?)");
pst.setString(1, matchId);
pst.setString(2, name);
pst.setTimestamp(3, birthdate);
pst.setString(4, bio);
pst.setString(5, accountId);
pst.executeUpdate();
}
finally
{
pst.close();
conn.close();
}
return exists;
}
Upvotes: 0
Views: 670
Reputation: 8200
Are you calling first isMatchIdInDatabase
then insertMatchId
for many records?
Possible duplicate: Efficient way to do batch INSERTS with JDBC
It is an expensive operation to open a connection and query for a single record. If you do that thousands of times, it gets very slow. You should try to restructure your query so that you only use one SELECT
. Then you can collect the records which you have to insert and doing it with batch insert.
Upvotes: 2
Reputation: 1389
You could try changing your SQL query that inserts the row to insert only if the row isn't in the database by using WHERE NOT EXISTS
.
This post seems to be relevant - I know it's for MySQL instead of PostgreSQL but the principles should be the same.
MySQL Conditional Insert
Upvotes: 0