java - Issue with android sql-query..."no such column"? -

i want use sql database store records game. don't have clue sql. have class "records" should manage in , output of records. additionally have class sqldatabasehelper provides sql-database.

my problem following line:

crsrecord = sqlitedatabase.rawquery(query_get_record + category, null); 

i got error "no such column: sys103" "sys103" name of category. don't know why can read. have idea?

sql table creation:

create table records (             id integer primary key autoincrement,             category varchar(30) not null,             displaytime varchar(12) not null,             recordtime varchar(10) not null); 

i guess writing works reading doesn't work.

public class records {             private sqliteopenhelper sqliteopenhelper;             private sqlitedatabase sqlitedatabase;              private static final string insert_new_record = "insert records(category, displayrecord, timerecord) values(";             private static final string query_get_record = "select *  records category = ";              public records(context context){                 sqliteopenhelper = new sqldatabasehelper(context);                 sqlitedatabase = sqliteopenhelper.getwritabledatabase();             }              public void addrecord(string category, string displaytime, string timerecord){                 contentvalues data = new contentvalues();                  data.put("category", category);                 data.put("displaytime", displaytime);                 data.put("recordtime", timerecord);                  sqlitedatabase.insert("records", null, data);         //      sqlitedatabase.execsql(insert_new_record + category + ", " + strtime + ", " + dbltime + ");");             }              public string[] getrecord(string category){                 string[] record = new string[3];                 cursor crsrecord;                 try{                     crsrecord = sqlitedatabase.rawquery(query_get_record + category, null);                 }catch(sqliteexception e){                     log.d("database", e.getmessage());                     string[] nullrecord = {category, "00:00.0", "0"};                     return nullrecord;                 }                  int i=0;                   while(crsrecord.movetonext()){                     record[i] = crsrecord.getstring(0);                     i++;                 }                  return record;              }         }      public class sqldatabasehelper extends sqliteopenhelper {         private context context;          public sqldatabasehelper(context context){             super(                 context,                 context.getresources().getstring(r.string.dbname),                 null,                 integer.parseint(context.getresources().getstring(r.string.version)));              this.context=context;          }          @override         public void oncreate(sqlitedatabase db) {             for(string sql : context.getresources().getstringarray(r.array.create)){                 db.execsql(sql);             }             log.d("database", "creat succesfully");          }          @override         public void onupgrade(sqlitedatabase db, int oldversion, int newversion) {          }     } 

my method data out of database, reason columnindex alway -1:

public string[] getrecord(string category){     string[] record = new string[3];     cursor crsrecord;          crsrecord = sqlitedatabase.rawquery(query_get_record, new string[]{ category } );      int i=0;     crsrecord.movetofirst();     while(!crsrecord.isafterlast()){          // instead of using int literal colum index,         // use getcolumnindex method         int index = crsrecord.getcolumnindex(category);         if (index == -1) {             string[] nullrecord = {category, "00:00.0", "0"};             return nullrecord;         }         else {             record[i] = crsrecord.getstring(index);             i++;         }          crsrecord.movetonext();     }        while(crsrecord.movetonext()){         record[i] = crsrecord.getstring(0);         i++;     }      return record;  } 

you'll need escape parameters.

as is, code executes query:

select *  records category = sys103 

that's not valid sql. should this:

select *  records category = 'sys103' 

and need escape apostrophes. you'd better off relying on rawquery escape parameters:

private static final string query_get_record                              = "select *  records category = ?"; 

and

crsrecord =      sqlitedatabase.rawquery(query_get_record, new string[]{ category } );