android - How to create a new column if not exist in ORMLite while DB Upgrade -

i using ormlite, , going release new version. have db upgrade script(json) this.

   {   "version": 9,   "ddlqueries": [     {       "querydescription": "add new column column name in tablename table",       "commandtype": "alter",       "table": "table name",       "column": {         "name": "column name",         "type": "blob"       }     },     {       "querydescription": "create new column column name in table name table",       "commandtype": "alter",       "table": "table name",       "column": {         "name": "column name",         "type": "text"       }     }   ] } 

and onupgrade method this.

public void onupgrade(object db, connectionsource connectionsource, int oldversion, int newversion) {         try {             while(++oldversion<=newversion) {                 assetmanager assetmanager = context.getassets();                 inputstream inputstream = assetmanager.open(migration_script_path + "version-" + oldversion + ".json");                 list<string> queries = new querybuilder().loadqueries(new inputstreamreader(inputstream));                 inputstream.close();                 (string sql : queries) {                     executesql(db, sql);                 }                 postupgrade(db, connectionsource, oldversion);             }         } catch (ioexception e) {             log.e(accountsdbhelper.class.getname(), "exception during onupgrade", e);             //below exception must thrown rollback changes.             throw new runtimeexception(e);         }     } 

now want check if column exists, if not exists want create new column otherwise want ignore.

how can that.

thanks.

i not sure whether can check existed column @ stage, have workaround problem.

here workaround!

public void onupgrade(object db, connectionsource connectionsource, int oldversion, int newversion) {         try {             while(++oldversion<=newversion) {                 if(oldversion == 9) {                     cursor cursor = rawquery(db,"pragma table_info(table_name)",null);                     int count = cursor.getcount();                     if(count > 0){                         boolean iscolumn1available = false;                         boolean iscolumn2available = false;                         while (cursor.movetonext()) {                             string columnname = cursor.getstring(1);                             if(columnname.equals("column1"))                                 iscolumn1available = true;                             if(columnname.equals("column2"))                                 iscolumn2available = true;                          }                        //here want skip if columns created                          if(iscolumn1available && iscolumn2available )                             return;                     }                 }                 assetmanager assetmanager = context.getassets();                 inputstream inputstream = assetmanager.open(migration_script_path + "version-" + oldversion + ".json");                 list<string> queries = new querybuilder().loadqueries(new inputstreamreader(inputstream));                 inputstream.close();                 (string sql : queries) {                     executesql(db, sql);                 }              }         } catch (ioexception e) {             log.e(accountsdbhelper.class.getname(), "exception during onupgrade", e);             //below exception must thrown rollback changes.             throw new runtimeexception(e);         }     } 

thanks.