diff --git a/fe/fe-core/src/main/java/org/apache/doris/analysis/DropDbStmt.java b/fe/fe-core/src/main/java/org/apache/doris/analysis/DropDbStmt.java
index 9b4f58efbf..08a1e630eb 100644
--- a/fe/fe-core/src/main/java/org/apache/doris/analysis/DropDbStmt.java
+++ b/fe/fe-core/src/main/java/org/apache/doris/analysis/DropDbStmt.java
@@ -17,9 +17,9 @@
 
 package org.apache.doris.analysis;
 
-import org.apache.doris.catalog.Database;
 import org.apache.doris.catalog.DatabaseIf;
 import org.apache.doris.catalog.Env;
+import org.apache.doris.catalog.MysqlCompatibleDatabase;
 import org.apache.doris.common.ErrorCode;
 import org.apache.doris.common.ErrorReport;
 import org.apache.doris.common.UserException;
@@ -62,7 +62,7 @@ public class DropDbStmt extends DdlStmt {
         InternalDatabaseUtil.checkDatabase(dbName, ConnectContext.get());
         // Don't allow to drop mysql compatible databases
         DatabaseIf db = Env.getCurrentInternalCatalog().getDbNullable(dbName);
-        if (db != null && (db instanceof Database) && ((Database) db).isMysqlCompatibleDatabase()) {
+        if (db != null && db instanceof MysqlCompatibleDatabase) {
             ErrorReport.reportAnalysisException(ErrorCode.ERR_DBACCESS_DENIED_ERROR,
                     analyzer.getQualifiedUser(), dbName);
         }
diff --git a/fe/fe-core/src/main/java/org/apache/doris/catalog/Database.java b/fe/fe-core/src/main/java/org/apache/doris/catalog/Database.java
index 71e61d5791..96db31af43 100644
--- a/fe/fe-core/src/main/java/org/apache/doris/catalog/Database.java
+++ b/fe/fe-core/src/main/java/org/apache/doris/catalog/Database.java
@@ -84,14 +84,14 @@ public class Database extends MetaObject implements Writable, DatabaseIf<Table>
     private long id;
     @SerializedName(value = "fullQualifiedName")
     private volatile String fullQualifiedName;
-    private ReentrantReadWriteLock rwLock;
+    private final ReentrantReadWriteLock rwLock;
 
     // table family group map
-    private Map<Long, Table> idToTable;
+    private final Map<Long, Table> idToTable;
     @SerializedName(value = "nameToTable")
     private Map<String, Table> nameToTable;
     // table name lower cast -> table name
-    private Map<String, String> lowerCaseToTableName;
+    private final Map<String, String> lowerCaseToTableName;
 
     // user define function
     @SerializedName(value = "name2Function")
@@ -893,11 +893,4 @@ public class Database extends MetaObject implements Writable, DatabaseIf<Table>
     public String toString() {
         return toJson();
     }
-
-    // Return ture if database is created for mysql compatibility.
-    // Currently, we have two dbs that are created for this purpose, InformationSchemaDb and MysqlDb,
-    public boolean isMysqlCompatibleDatabase() {
-        return false;
-    }
-
 }
diff --git a/fe/fe-core/src/main/java/org/apache/doris/catalog/DatabaseIf.java b/fe/fe-core/src/main/java/org/apache/doris/catalog/DatabaseIf.java
index 3ba2957337..e80f335be1 100644
--- a/fe/fe-core/src/main/java/org/apache/doris/catalog/DatabaseIf.java
+++ b/fe/fe-core/src/main/java/org/apache/doris/catalog/DatabaseIf.java
@@ -273,5 +273,5 @@ public interface DatabaseIf<T extends TableIf> {
         return -1L;
     }
 
-    public Map<Long, TableIf> getIdToTable();
+    Map<Long, TableIf> getIdToTable();
 }
diff --git a/fe/fe-core/src/main/java/org/apache/doris/catalog/MysqlCompatibleDatabase.java b/fe/fe-core/src/main/java/org/apache/doris/catalog/MysqlCompatibleDatabase.java
index 1d4aa62dc9..12d915321e 100644
--- a/fe/fe-core/src/main/java/org/apache/doris/catalog/MysqlCompatibleDatabase.java
+++ b/fe/fe-core/src/main/java/org/apache/doris/catalog/MysqlCompatibleDatabase.java
@@ -77,11 +77,6 @@ public abstract class MysqlCompatibleDatabase extends Database {
         throw new IOException("Not support.");
     }
 
-    @Override
-    public boolean isMysqlCompatibleDatabase() {
-        return true;
-    }
-
     /**
      * This method must be re-implemented since {@link Env#createView(CreateViewStmt)}
      * will call this method. And create view should not succeed under this database.
diff --git a/fe/fe-core/src/main/java/org/apache/doris/clone/TabletChecker.java b/fe/fe-core/src/main/java/org/apache/doris/clone/TabletChecker.java
index c6f6be3d46..66497e7d18 100644
--- a/fe/fe-core/src/main/java/org/apache/doris/clone/TabletChecker.java
+++ b/fe/fe-core/src/main/java/org/apache/doris/clone/TabletChecker.java
@@ -23,6 +23,7 @@ import org.apache.doris.catalog.Database;
 import org.apache.doris.catalog.Env;
 import org.apache.doris.catalog.MaterializedIndex;
 import org.apache.doris.catalog.MaterializedIndex.IndexExtState;
+import org.apache.doris.catalog.MysqlCompatibleDatabase;
 import org.apache.doris.catalog.OlapTable;
 import org.apache.doris.catalog.Partition;
 import org.apache.doris.catalog.Partition.PartitionState;
@@ -280,7 +281,7 @@ public class TabletChecker extends MasterDaemon {
                 continue;
             }
 
-            if (db.isMysqlCompatibleDatabase()) {
+            if (db instanceof MysqlCompatibleDatabase) {
                 continue;
             }
 
diff --git a/fe/fe-core/src/main/java/org/apache/doris/datasource/CatalogIf.java b/fe/fe-core/src/main/java/org/apache/doris/datasource/CatalogIf.java
index c8f3033c66..7fd240aa8d 100644
--- a/fe/fe-core/src/main/java/org/apache/doris/datasource/CatalogIf.java
+++ b/fe/fe-core/src/main/java/org/apache/doris/datasource/CatalogIf.java
@@ -172,9 +172,9 @@ public interface CatalogIf<T extends DatabaseIf> {
     }
 
     // Return a copy of all db collection.
-    public Collection<DatabaseIf<? extends TableIf>> getAllDbs();
+    Collection<DatabaseIf<? extends TableIf>> getAllDbs();
 
-    public boolean enableAutoAnalyze();
+    boolean enableAutoAnalyze();
 
-    public ConcurrentHashMap<Long, DatabaseIf> getIdToDb();
+    ConcurrentHashMap<Long, DatabaseIf> getIdToDb();
 }
diff --git a/fe/fe-core/src/main/java/org/apache/doris/datasource/InternalCatalog.java b/fe/fe-core/src/main/java/org/apache/doris/datasource/InternalCatalog.java
index 3212d18c1d..47ea998bcb 100644
--- a/fe/fe-core/src/main/java/org/apache/doris/datasource/InternalCatalog.java
+++ b/fe/fe-core/src/main/java/org/apache/doris/datasource/InternalCatalog.java
@@ -839,8 +839,8 @@ public class InternalCatalog implements CatalogIf<Database> {
         LOG.info("begin to drop table: {} from db: {}, is force: {}", tableName, dbName, stmt.isForceDrop());
 
         // check database
-        Database db = (Database) getDbOrDdlException(dbName);
-        if (db.isMysqlCompatibleDatabase()) {
+        Database db = getDbOrDdlException(dbName);
+        if (db instanceof MysqlCompatibleDatabase) {
             throw new DdlException("Drop table from this database is not allowed.");
         }
 
@@ -1066,7 +1066,7 @@ public class InternalCatalog implements CatalogIf<Database> {
         // check if db exists
         Database db = getDbOrDdlException(dbName);
         // InfoSchemaDb and MysqlDb can not create table manually
-        if (db.isMysqlCompatibleDatabase()) {
+        if (db instanceof MysqlCompatibleDatabase) {
             ErrorReport.reportDdlException(ErrorCode.ERR_CANT_CREATE_TABLE, tableName,
                     ErrorCode.ERR_CANT_CREATE_TABLE.getCode(), "not supported create table in this database");
         }
@@ -3227,7 +3227,7 @@ public class InternalCatalog implements CatalogIf<Database> {
         for (Map.Entry<Long, Database> entry : idToDb.entrySet()) {
             Database db = entry.getValue();
             // Don't write internal database meta.
-            if (!db.isMysqlCompatibleDatabase()) {
+            if (!(db instanceof MysqlCompatibleDatabase)) {
                 checksum ^= entry.getKey();
                 db.write(dos);
             }
@@ -3246,7 +3246,7 @@ public class InternalCatalog implements CatalogIf<Database> {
             Database dbPrev = fullNameToDb.get(db.getFullName());
             if (dbPrev != null) {
                 String errMsg;
-                if (dbPrev.isMysqlCompatibleDatabase() || db.isMysqlCompatibleDatabase()) {
+                if (dbPrev instanceof MysqlCompatibleDatabase || db instanceof MysqlCompatibleDatabase) {
                     errMsg = String.format(
                         "Mysql compatibility problem, previous checkpoint already has a database with full name "
                         + "%s. If its name is mysql, try to add mysqldb_replace_name=\"mysql_comp\" in fe.conf.",
diff --git a/fe/fe-core/src/main/java/org/apache/doris/httpv2/rest/ShowAction.java b/fe/fe-core/src/main/java/org/apache/doris/httpv2/rest/ShowAction.java
index 6db2a7e7b5..0aa5dd54d7 100644
--- a/fe/fe-core/src/main/java/org/apache/doris/httpv2/rest/ShowAction.java
+++ b/fe/fe-core/src/main/java/org/apache/doris/httpv2/rest/ShowAction.java
@@ -20,6 +20,7 @@ package org.apache.doris.httpv2.rest;
 import org.apache.doris.catalog.Database;
 import org.apache.doris.catalog.DatabaseIf;
 import org.apache.doris.catalog.Env;
+import org.apache.doris.catalog.MysqlCompatibleDatabase;
 import org.apache.doris.catalog.OlapTable;
 import org.apache.doris.catalog.Table;
 import org.apache.doris.catalog.TableIf.TableType;
@@ -199,7 +200,7 @@ public class ShowAction extends RestBaseController {
         } else {
             for (long dbId : Env.getCurrentInternalCatalog().getDbIds()) {
                 DatabaseIf db = Env.getCurrentInternalCatalog().getDbNullable(dbId);
-                if (db == null || !(db instanceof Database) || ((Database) db).isMysqlCompatibleDatabase()) {
+                if (db == null || !(db instanceof Database) || db instanceof MysqlCompatibleDatabase) {
                     continue;
                 }
                 totalSize += getDataSizeOfDatabase(db);
@@ -232,7 +233,7 @@ public class ShowAction extends RestBaseController {
         } else {
             for (long dbId : Env.getCurrentInternalCatalog().getDbIds()) {
                 DatabaseIf db = Env.getCurrentInternalCatalog().getDbNullable(dbId);
-                if (db == null || !(db instanceof Database) || ((Database) db).isMysqlCompatibleDatabase()) {
+                if (db == null || !(db instanceof Database) || ((Database) db) instanceof MysqlCompatibleDatabase) {
                     continue;
                 }
                 Map<String, Long> tablesEntry = getDataSizeOfTables(db, tableName, singleReplicaBool);
diff --git a/fe/fe-core/src/main/java/org/apache/doris/master/PartitionInMemoryInfoCollector.java b/fe/fe-core/src/main/java/org/apache/doris/master/PartitionInMemoryInfoCollector.java
index 22f2d41cfa..77ed582979 100644
--- a/fe/fe-core/src/main/java/org/apache/doris/master/PartitionInMemoryInfoCollector.java
+++ b/fe/fe-core/src/main/java/org/apache/doris/master/PartitionInMemoryInfoCollector.java
@@ -19,6 +19,7 @@ package org.apache.doris.master;
 
 import org.apache.doris.catalog.Database;
 import org.apache.doris.catalog.Env;
+import org.apache.doris.catalog.MysqlCompatibleDatabase;
 import org.apache.doris.catalog.OlapTable;
 import org.apache.doris.catalog.Partition;
 import org.apache.doris.catalog.Table;
@@ -56,7 +57,7 @@ public class PartitionInMemoryInfoCollector extends MasterDaemon {
                 LOG.warn("Database [" + dbId + "] does not exist, skip to update database used data quota");
                 continue;
             }
-            if (db.isMysqlCompatibleDatabase()) {
+            if (db instanceof MysqlCompatibleDatabase) {
                 continue;
             }
             try {
diff --git a/fe/fe-core/src/main/java/org/apache/doris/transaction/DbUsedDataQuotaInfoCollector.java b/fe/fe-core/src/main/java/org/apache/doris/transaction/DbUsedDataQuotaInfoCollector.java
index 87d509bbb4..3a713bdc63 100644
--- a/fe/fe-core/src/main/java/org/apache/doris/transaction/DbUsedDataQuotaInfoCollector.java
+++ b/fe/fe-core/src/main/java/org/apache/doris/transaction/DbUsedDataQuotaInfoCollector.java
@@ -19,6 +19,7 @@ package org.apache.doris.transaction;
 
 import org.apache.doris.catalog.Database;
 import org.apache.doris.catalog.Env;
+import org.apache.doris.catalog.MysqlCompatibleDatabase;
 import org.apache.doris.common.AnalysisException;
 import org.apache.doris.common.Config;
 import org.apache.doris.common.util.MasterDaemon;
@@ -50,7 +51,7 @@ public class DbUsedDataQuotaInfoCollector extends MasterDaemon {
                 LOG.warn("Database [" + dbId + "] does not exist, skip to update database used data quota");
                 continue;
             }
-            if (db.isMysqlCompatibleDatabase()) {
+            if (db instanceof MysqlCompatibleDatabase) {
                 continue;
             }
             try {
diff --git a/fe/fe-core/src/test/java/org/apache/doris/clone/RebalancerTestUtil.java b/fe/fe-core/src/test/java/org/apache/doris/clone/RebalancerTestUtil.java
index da03d42a64..063faf2d3b 100644
--- a/fe/fe-core/src/test/java/org/apache/doris/clone/RebalancerTestUtil.java
+++ b/fe/fe-core/src/test/java/org/apache/doris/clone/RebalancerTestUtil.java
@@ -21,6 +21,7 @@ import org.apache.doris.catalog.Database;
 import org.apache.doris.catalog.DiskInfo;
 import org.apache.doris.catalog.Env;
 import org.apache.doris.catalog.MaterializedIndex;
+import org.apache.doris.catalog.MysqlCompatibleDatabase;
 import org.apache.doris.catalog.OlapTable;
 import org.apache.doris.catalog.Partition;
 import org.apache.doris.catalog.Replica;
@@ -145,7 +146,7 @@ public class RebalancerTestUtil {
                 continue;
             }
 
-            if (db.isMysqlCompatibleDatabase()) {
+            if (db instanceof MysqlCompatibleDatabase) {
                 continue;
             }