diff --git a/mybatis-flex-core/src/main/java/com/mybatisflex/core/dialect/CommonsDialectImpl.java b/mybatis-flex-core/src/main/java/com/mybatisflex/core/dialect/CommonsDialectImpl.java
index 843c6dec..40f324e7 100644
--- a/mybatis-flex-core/src/main/java/com/mybatisflex/core/dialect/CommonsDialectImpl.java
+++ b/mybatis-flex-core/src/main/java/com/mybatisflex/core/dialect/CommonsDialectImpl.java
@@ -280,7 +280,7 @@ public class CommonsDialectImpl implements IDialect {
                 index++;
             }
         }
-        sqlBuilder.append(" FROM ").append(StringUtil.join(",", queryTables, queryTable -> queryTable.toSql(this)));
+        sqlBuilder.append(" FROM ").append(StringUtil.join(", ", queryTables, queryTable -> queryTable.toSql(this)));
 
         buildJoinSql(sqlBuilder, queryWrapper, allTables);
         buildWhereSql(sqlBuilder, queryWrapper, allTables);
@@ -306,7 +306,7 @@ public class CommonsDialectImpl implements IDialect {
 
         //ignore selectColumns
         StringBuilder sqlBuilder = new StringBuilder("SELECT COUNT(*) FROM ");
-        sqlBuilder.append(StringUtil.join(",", queryTables, queryTable -> queryTable.toSql(this)));
+        sqlBuilder.append(StringUtil.join(", ", queryTables, queryTable -> queryTable.toSql(this)));
 
 
         buildJoinSql(sqlBuilder, queryWrapper, allTables);
@@ -329,7 +329,7 @@ public class CommonsDialectImpl implements IDialect {
 
         //ignore selectColumns
         StringBuilder sqlBuilder = new StringBuilder("DELETE FROM ");
-        sqlBuilder.append(StringUtil.join(",", queryTables, queryTable -> queryTable.toSql(this)));
+        sqlBuilder.append(StringUtil.join(", ", queryTables, queryTable -> queryTable.toSql(this)));
 
         buildJoinSql(sqlBuilder, queryWrapper, allTables);
         buildWhereSql(sqlBuilder, queryWrapper, allTables);
diff --git a/mybatis-flex-core/src/main/java/com/mybatisflex/core/query/DistinctQueryColumn.java b/mybatis-flex-core/src/main/java/com/mybatisflex/core/query/DistinctQueryColumn.java
index 5aa5f96e..bfa67e45 100644
--- a/mybatis-flex-core/src/main/java/com/mybatisflex/core/query/DistinctQueryColumn.java
+++ b/mybatis-flex-core/src/main/java/com/mybatisflex/core/query/DistinctQueryColumn.java
@@ -34,7 +34,7 @@ public class DistinctQueryColumn extends QueryColumn {
         if (CollectionUtil.isEmpty(queryTables)) {
             return "";
         }
-        return " DISTINCT " + StringUtil.join(",", queryColumns, queryColumn ->
+        return " DISTINCT " + StringUtil.join(", ", queryColumns, queryColumn ->
                 queryColumn.toSelectSql(queryTables, dialect));
     }
 }