String getTblKey() {
      Table tbl = this.t;
      String catName = tbl.getCatName();
      String dbName = tbl.getDbName();
      String tblName = tbl.getTableName();
      return CacheUtils.buildTableKey(catName, dbName, tblName);
    }
this flag is used to validate/invalidate cached constraints snapshot.
All table constraints are update successfully either via updater thread or
while create_table_with_constraint api then it is set to true else
false and redirect all the call to raw metastore.
standalone-metastore/metastore-server/src/main/java/org/apache/hadoop/hive/metastore/cache/SharedCache.java