Using a Query

Syntax Syntax

```
report  DEMO_QUERY_PERSISTENT.
```

parameters AIRPFROM type S_FROMAIRP default 'FRA'.

parameters AIRPTO   type S_TOAIRP   default 'SIN'.

data: QUERY_MANAGER type ref to IF_OS_QUERY_MANAGER,

      QUERY         type ref to IF_OS_QUERY.

```
data: CONNECTIONS type OSREFTAB,
```

      CONNECTION  type ref to CL_SPFLI_PERSISTENT,

      AGENT       type ref to CA_SPFLI_PERSISTENT.

```
data: CARRID type S_CARR_ID,
```
```
      CONNID type S_CONN_ID.
```
```
data: TMP type ref to OBJECT.
```
```
data: EXC type ref to CX_ROOT,
```
```
      TEXT type STRING.
```
```
AGENT = CA_SPFLI_PERSISTENT=>AGENT.
```
```
try.
```

    QUERY_MANAGER = CL_OS_SYSTEM=>GET_QUERY_MANAGER( ).

    QUERY = QUERY_MANAGER->CREATE_QUERY(

              I_FILTER  = `AIRPFROM = PAR1 AND AIRPTO = PAR2` ).

```
    CONNECTIONS =
```

      AGENT->IF_OS_CA_PERSISTENCY~GET_PERSISTENT_BY_QUERY(

```
               I_QUERY   = QUERY
```
```
               I_PAR1    = AIRPFROM
```
```
               I_PAR2    = AIRPTO ).
```
```
    if ( lines( CONNECTIONS ) > 0 ).
```

      read table CONNECTIONS into TMP index 1.

```
      CONNECTION ?= TMP.
```

      CARRID = CONNECTION->GET_CARRID( ).

      CONNID = CONNECTION->GET_CONNID( ).

      concatenate TEXT-001 CARRID CONNID into TEXT separated by SPACE.

```
    else.
```
```
      TEXT = TEXT-002.
```
```
    endif.
```
```
    message TEXT type 'I'.
```
```
  catch CX_ROOT into EXC.
```
```
    TEXT = EXC->GET_TEXT( ).
```
```
    message TEXT type 'I'.
```
```
endtry.
```

End of the code.

A reference to the class actor of persistent class CL_SPFLI_PERSISTENT is assigned to the reference variable AGENT. The static constructor of the class CA_SPFLI_PERSISTENT generates this reference once only. A Query Manager is obtained using method GET_QUERY_MANAGER of system class CL_OS_SYSTEM, and a query is created using method CREATE_QUERY when you specify the filter. The query is executed with interface method GET_PERSISTENT_BY_QUERY of interface IF_OS_CA_PERSISTENCY, and the first flight that is found is displayed.