Failure/foul-magics
1
0
Fork 0
forked from External/mage
Code Pull requests Releases Packages Activity Actions

SQL query perfomance improvements

Browse source 
There will be always 0 or 1 distinct result. If we don't limit this query it will find an item, and still will go through the whole table trying another one, which is unneccesary and have performance impact.
This commit is contained in:
vraskulin 2016-12-16 17:27:19 +03:00
parent 1d989a70db
commit 3be7598ee1
3 changed files with 20 additions and 23 deletions
Download patch file Download diff file Expand all files Collapse all files

17
Mage.Server/src/main/java/mage/server/record/UserStatsRepository.java
View file

@ -7,17 +7,18 @@ import com.j256.ormlite.stmt.QueryBuilder;
import com.j256.ormlite.support.ConnectionSource;
import com.j256.ormlite.support.DatabaseConnection;
import com.j256.ormlite.table.TableUtils;
import java.io.File;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.HashSet;
import java.util.List;
import mage.cards.repository.RepositoryUtil;
import mage.game.result.ResultProtos;
import mage.server.rating.GlickoRating;
import mage.server.rating.GlickoRatingSystem;
import org.apache.log4j.Logger;
import java.io.File;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.HashSet;
import java.util.List;
public enum UserStatsRepository {
instance;
@ -68,7 +69,7 @@ public enum UserStatsRepository {
public UserStats getUser(String userName) {
try {
QueryBuilder<UserStats, Object> qb = dao.queryBuilder();
qb.where().eq("userName", userName);
qb.limit(1L).where().eq("userName", userName);
List<UserStats> users = dao.query(qb.prepare());
if (users.size() == 1) {
return users.get(0);
@ -92,7 +93,7 @@ public enum UserStatsRepository {
public long getLatestEndTimeMs() {
try {
QueryBuilder<UserStats, Object> qb = dao.queryBuilder();
qb.orderBy("endTimeMs", false).limit(1);
qb.orderBy("endTimeMs", false).limit(1L);
List<UserStats> users = dao.query(qb.prepare());
if (users.size() == 1) {
return users.get(0).getEndTimeMs();
@ -106,7 +107,7 @@ public enum UserStatsRepository {
// updateUserStats reads tables finished after the last DB update and reflects it to the DB.
// It returns the list of user names that are upated.
public List<String> updateUserStats() {
HashSet<String> updatedUsers = new HashSet();
HashSet<String> updatedUsers = new HashSet<>();
// Lock the DB so that no other updateUserStats runs at the same time.
synchronized(this) {
long latestEndTimeMs = this.getLatestEndTimeMs();