[#860] Fixed MySQL errno 150

Fixed by disabling foreign key checks before applying patches and
enabling afterwards.

Error was caused by re-creation of plan_sessions table during
plan_world_times creation (This was done by the database engine),
but plan_sessions was referenced by temp_world_times and so could not
be recreated as those references would become invalid.

Plan/common/src/main/java/com/djrapitops/plan/system/database/databases/sql/patches/DiskUsagePatch.java

@@ -31,7 +31,7 @@ public class DiskUsagePatch extends Patch {
     }
 
     @Override
-    public void apply() {
+    protected void applyPatch() {
         addColumn(TPSTable.TABLE_NAME,
                 TPSTable.Col.FREE_DISK + " bigint NOT NULL DEFAULT -1"
         );

Plan/common/src/main/java/com/djrapitops/plan/system/database/databases/sql/patches/GeoInfoLastUsedPatch.java

@@ -31,7 +31,7 @@ public class GeoInfoLastUsedPatch extends Patch {
     }
 
     @Override
-    public void apply() {
+    protected void applyPatch() {
         addColumn(GeoInfoTable.TABLE_NAME,
                 GeoInfoTable.Col.LAST_USED + " bigint NOT NULL DEFAULT 0"
         );

Plan/common/src/main/java/com/djrapitops/plan/system/database/databases/sql/patches/GeoInfoOptimizationPatch.java

@@ -41,7 +41,7 @@ public class GeoInfoOptimizationPatch extends Patch {
     }
 
     @Override
-    public void apply() {
+    protected void applyPatch() {
         try {
             tempOldTable();
             db.getGeoInfoTable().createTable();

Plan/common/src/main/java/com/djrapitops/plan/system/database/databases/sql/patches/IPAnonPatch.java

@@ -68,7 +68,7 @@ public class IPAnonPatch extends Patch {
     }
 
     @Override
-    public void apply() {
+    protected void applyPatch() {
         Map<UUID, List<GeoInfo>> allGeoInfo = db.getGeoInfoTable().getAllGeoInfo();
         anonymizeIPs(allGeoInfo);
         groupHashedIPs();

Plan/common/src/main/java/com/djrapitops/plan/system/database/databases/sql/patches/IPHashPatch.java

@@ -31,7 +31,7 @@ public class IPHashPatch extends Patch {
     }
 
     @Override
-    public void apply() {
+    protected void applyPatch() {
         addColumn(GeoInfoTable.TABLE_NAME, GeoInfoTable.Col.IP_HASH.get() + " varchar(200) DEFAULT ''");
     }
 }

Plan/common/src/main/java/com/djrapitops/plan/system/database/databases/sql/patches/KillsOptimizationPatch.java

@@ -44,7 +44,7 @@ public class KillsOptimizationPatch extends Patch {
     }
 
     @Override
-    public void apply() {
+    protected void applyPatch() {
         try {
             tempOldTable();
             db.getKillsTable().createTable();

Plan/common/src/main/java/com/djrapitops/plan/system/database/databases/sql/patches/KillsServerIDPatch.java

@@ -58,7 +58,7 @@ public class KillsServerIDPatch extends Patch {
     }
 
     @Override
-    public void apply() {
+    protected void applyPatch() {
         addColumn(KillsTable.TABLE_NAME, "server_id integer NOT NULL DEFAULT 0");
 
         Map<Integer, Integer> sessionIDServerIDRelation = db.getSessionsTable().getIDServerIDRelation();

Plan/common/src/main/java/com/djrapitops/plan/system/database/databases/sql/patches/NicknameLastSeenPatch.java

@@ -41,7 +41,7 @@ public class NicknameLastSeenPatch extends Patch {
     }
 
     @Override
-    public void apply() {
+    protected void applyPatch() {
         addColumn(NicknamesTable.TABLE_NAME,
                 NicknamesTable.Col.LAST_USED + " bigint NOT NULL DEFAULT '0'"
         );

Plan/common/src/main/java/com/djrapitops/plan/system/database/databases/sql/patches/NicknamesOptimizationPatch.java

@@ -42,7 +42,7 @@ public class NicknamesOptimizationPatch extends Patch {
     }
 
     @Override
-    public void apply() {
+    protected void applyPatch() {
         try {
             tempOldTable();
             db.getNicknamesTable().createTable();

Plan/common/src/main/java/com/djrapitops/plan/system/database/databases/sql/patches/Patch.java

@@ -45,7 +45,21 @@ public abstract class Patch {
 
     public abstract boolean hasBeenApplied();
 
-    public abstract void apply();
+    protected abstract void applyPatch();
+
+    public void apply() {
+        if (dbType == DBType.MYSQL) disableForeignKeyChecks();
+        applyPatch();
+        if (dbType == DBType.MYSQL) enableForeignKeyChecks();
+    }
+
+    private void enableForeignKeyChecks() {
+        db.execute("SET FOREIGN_KEY_CHECKS=1");
+    }
+
+    private void disableForeignKeyChecks() {
+        db.execute("SET FOREIGN_KEY_CHECKS=0");
+    }
 
     public <T> T query(QueryStatement<T> query) {
         return db.query(query);

Plan/common/src/main/java/com/djrapitops/plan/system/database/databases/sql/patches/PingOptimizationPatch.java

@@ -42,7 +42,7 @@ public class PingOptimizationPatch extends Patch {
     }
 
     @Override
-    public void apply() {
+    protected void applyPatch() {
         try {
             tempOldTable();
             db.getPingTable().createTable();

Plan/common/src/main/java/com/djrapitops/plan/system/database/databases/sql/patches/SessionAFKTimePatch.java

@@ -31,7 +31,7 @@ public class SessionAFKTimePatch extends Patch {
     }
 
     @Override
-    public void apply() {
+    protected void applyPatch() {
         addColumn(SessionsTable.TABLE_NAME,
                 SessionsTable.Col.AFK_TIME + " bigint NOT NULL DEFAULT 0"
         );

Plan/common/src/main/java/com/djrapitops/plan/system/database/databases/sql/patches/SessionsOptimizationPatch.java

@@ -42,7 +42,7 @@ public class SessionsOptimizationPatch extends Patch {
     }
 
     @Override
-    public void apply() {
+    protected void applyPatch() {
         try {
             dropForeignKeys(tableName);
             ensureNoForeignKeyConstraints(tableName);

Plan/common/src/main/java/com/djrapitops/plan/system/database/databases/sql/patches/TransferTableRemovalPatch.java

@@ -30,7 +30,7 @@ public class TransferTableRemovalPatch extends Patch {
     }
 
     @Override
-    public void apply() {
+    protected void applyPatch() {
         dropTable("plan_transfer");
     }
 }

Plan/common/src/main/java/com/djrapitops/plan/system/database/databases/sql/patches/UserInfoOptimizationPatch.java

@@ -42,7 +42,7 @@ public class UserInfoOptimizationPatch extends Patch {
     }
 
     @Override
-    public void apply() {
+    protected void applyPatch() {
         try {
             tempOldTable();
             db.getUserInfoTable().createTable();

Plan/common/src/main/java/com/djrapitops/plan/system/database/databases/sql/patches/Version10Patch.java

@@ -37,7 +37,7 @@ public class Version10Patch extends Patch {
     }
 
     @Override
-    public void apply() {
+    protected void applyPatch() {
         try {
             Optional<Integer> fetchedServerID = db.getServerTable().getServerID(getServerUUID());
             if (!fetchedServerID.isPresent()) {

Plan/common/src/main/java/com/djrapitops/plan/system/database/databases/sql/patches/VersionTableRemovalPatch.java

@@ -30,7 +30,7 @@ public class VersionTableRemovalPatch extends Patch {
     }
 
     @Override
-    public void apply() {
+    protected void applyPatch() {
         dropTable("plan_version");
     }
 }

Plan/common/src/main/java/com/djrapitops/plan/system/database/databases/sql/patches/WorldTimesOptimizationPatch.java

@@ -43,7 +43,7 @@ public class WorldTimesOptimizationPatch extends Patch {
     }
 
     @Override
-    public void apply() {
+    protected void applyPatch() {
         try {
             tempOldTable();
             db.getWorldTimesTable().createTable();

Plan/common/src/main/java/com/djrapitops/plan/system/database/databases/sql/patches/WorldTimesSeverIDPatch.java

@@ -59,7 +59,7 @@ public class WorldTimesSeverIDPatch extends Patch {
     }
 
     @Override
-    public void apply() {
+    protected void applyPatch() {
         Map<Integer, Integer> sessionIDServerIDRelation = db.getSessionsTable().getIDServerIDRelation();
 
         String sql = "UPDATE " + WorldTimesTable.TABLE_NAME + " SET " +

Plan/common/src/main/java/com/djrapitops/plan/system/database/databases/sql/patches/WorldsOptimizationPatch.java

@@ -41,7 +41,7 @@ public class WorldsOptimizationPatch extends Patch {
     }
 
     @Override
-    public void apply() {
+    protected void applyPatch() {
         try {
             dropForeignKeys(tableName);
             ensureNoForeignKeyConstraints(tableName);

Plan/common/src/main/java/com/djrapitops/plan/system/database/databases/sql/patches/WorldsServerIDPatch.java

@@ -64,7 +64,7 @@ public class WorldsServerIDPatch extends Patch {
     }
 
     @Override
-    public void apply() {
+    protected void applyPatch() {
         WorldTable worldTable = db.getWorldTable();
 
         List<UUID> serverUUIDs = db.getServerTable().getServerUUIDs();

Plan/common/src/test/java/com/djrapitops/plan/system/database/databases/sql/CommonDBTest.java

@@ -111,7 +111,7 @@ public abstract class CommonDBTest {
             }
 
             @Override
-            public void apply() {
+            public void applyPatch() {
                 dropTable("plan_world_times");
                 dropTable("plan_kills");
                 dropTable("plan_sessions");