I'm fairly new to SQL server...but I have a problem. I've written the below query, which works just fine for displaying all visits (encounters) and lab results for a patient in 2012. 

```
SELECT pat.patient_id, pat.last_name, Pat.first_name, pat.ethnic_group,
pat.race, pl.icdcode, enc.encounter_date, lab.test_performed, lab.result_value,
lab.result_units
FROM dbo.dem_patient pat
RIGHT JOIN dbo.med_problemlist as pl
ON pat.patient_id = pl.patient_id
JOIN dbo.enc_encounter as enc
ON pat.patient_id = enc.patient_id
JOIN dbo.med_labresult as lab
ON pat.patient_id = lab.patient_id
WHERE pl.icdcode like '401.9%' AND
enc.encounter_date >= '01/01/2012' AND enc.encounter_date <= '12/31/2012' AND
pat.last_name != 'test' AND (lab.test_performed = 'HgbA1c' OR 
lab.test_performed = 'Hemoglobin A1c')
GROUP BY pat.patient_id, pat.last_name, Pat.first_name, pat.ethnic_group,
pat.race, pl.icdcode, enc.encounter_date, lab.test_performed, lab.result_value,
lab.result_units
ORDER BY race, ethnic_group

```

The result from the above query looks something like this:

```
patient_id  last_name  first_name  ethnic_group  race  icdcode  encounter_date lab_result
0           smith      john        HIS           WHI   401.90   01/01/2012     9.1
0           smith      john        HIS           WHI   401.90   10/12/2012     9.2
0           smith      john        HIS           WHI   401.90   11/15/2012     9.7
5           doe        jane        NSP           BLK   401.90   01/20/2012     11
6           davids     david       NSP           BLK   401.90   04/25/2012     5.9
6           davids     david       NSP           BLK   401.90   05/04/2012     6.4

```

However, I now need to return only those patients who have more than one visit (encounter) between 1/1/2012 and 12/31/2012. It would look like this (from the above result)

```
patient_id  last_name  first_name  ethnic_group  race  icdcode  encounter_date lab_result
0           smith      john        HIS           WHI   401.90   01/01/2012     9.1
6           davids     david       NSP           BLK   401.90   04/25/2012     5.9

```

Can anyone help me with this? 

UPDATE: So, using the suggestions below, I've added HAVING COUNT(\*) > 1 to the query. However, that gives me some results I don't quite understand. 

Results of query without the HAVING COUNT(\*) > 1 statement:

```
1001131     BLA 401.9   48:48.3 Hemoglobin A1c  9.9
1001131     BLA 401.9   00:00.0 Hemoglobin A1c  9.9
1001131     BLA 401.9   44:44.3 Hemoglobin A1c  9.9
1001648     BLA 401.9   50:15.6 Hemoglobin A1c  6.5
1001648     BLA 401.9   16:15.1 Hemoglobin A1c  6.5
1001648     BLA 401.9   28:04.5 Hemoglobin A1c  6.5
1001648     BLA 401.9   17:00.2 Hemoglobin A1c  6.5
1002648     BLA 401.9   17:47.8 Hemoglobin A1c  6.1
1002648     BLA 401.9   52:38.0 Hemoglobin A1c  6.1
1002648     BLA 401.9   43:47.3 Hemoglobin A1c  6.1
1002648     BLA 401.9   02:55.9 Hemoglobin A1c  6.1
1002715     BLA 401.9   37:52.4 Hemoglobin A1c  13.1
1002715     BLA 401.9   44:41.0 Hemoglobin A1c  12.6
1002715     BLA 401.9   44:41.0 Hemoglobin A1c  13.1
1002715     BLA 401.9   37:52.4 Hemoglobin A1c  10.7
1002715     BLA 401.9   37:52.4 Hemoglobin A1c  12.6
1002715     BLA 401.9   00:57.9 Hemoglobin A1c  10.7
1002715     BLA 401.9   00:57.9 Hemoglobin A1c  12.6
1002715     BLA 401.9   00:57.9 Hemoglobin A1c  13.1
1002715     BLA 401.9   38:17.6 Hemoglobin A1c  10.7
1002715     BLA 401.9   38:17.6 Hemoglobin A1c  12.6
1002715     BLA 401.9   38:17.6 Hemoglobin A1c  13.1
1002715     BLA 401.9   44:41.0 Hemoglobin A1c  10.7
1002893     BLA 401.9   33:45.4 Hemoglobin A1c  5.9
1002893     BLA 401.9   22:58.5 Hemoglobin A1c  5.9
1002893     BLA 401.9   00:00.0 Hemoglobin A1c  5.9
1002893     BLA 401.9   55:11.3 Hemoglobin A1c  5.9
1003195     BLA 401.9   34:08.7 Hemoglobin A1c  6.4
1003195     BLA 401.9   50:03.6 Hemoglobin A1c  6.4
1003195     BLA 401.9   08:36.8 Hemoglobin A1c  6.4
1003195     BLA 401.9   33:56.6 Hemoglobin A1c  6.4
1003195     BLA 401.9   34:04.3 Hemoglobin A1c  6.4

```

Results of query with the HAVING statement:

```
1001937     BLA 401.9   11/14/12Hemoglobin A1c  6.3
1001937     BLA 401.9   8/14/12 Hemoglobin A1c  6.3
1001937     BLA 401.9   5/14/12 Hemoglobin A1c  6.3
1001937     BLA 401.9   2/14/12 Hemoglobin A1c  6.3
1001937     BLA 401.9   11/14/12Hemoglobin A1c  6.3
1002034     BLA 401.9   1/10/12 HEMOGLOBIN A1c  7.7
1002034     BLA 401.9   6/8/12  HEMOGLOBIN A1c  7.7
1002034     BLA 401.9   9/7/12  HEMOGLOBIN A1c  7.7
1002034     BLA 401.9   10/15/12HEMOGLOBIN A1c  7.7
1002648     BLA 401.9   2/22/12 Hemoglobin A1c  6.1
1002648     BLA 401.9   7/2/12  Hemoglobin A1c  6.1
1002648     BLA 401.9   10/2/12 Hemoglobin A1c  6.1
1002648     BLA 401.9   2/22/12 Hemoglobin A1c  6.1
1020923     BLA 401.9   1/30/12 HEMOGLOBIN A1c  10
1020923     BLA 401.9   1/30/12 Hemoglobin A1c  11.8
1020923     BLA 401.9   4/17/12 Hemoglobin A1c  11.8
1020923     BLA 401.9   5/16/12 HEMOGLOBIN A1c  10
1020923     BLA 401.9   5/16/12 Hemoglobin A1c  11.8
1020923     BLA 401.9   9/13/12 HEMOGLOBIN A1c  10
1020923     BLA 401.9   9/13/12 Hemoglobin A1c  9.3
1020923     BLA 401.9   10/1/12 HEMOGLOBIN A1c  10
1020923     BLA 401.9   10/1/12 Hemoglobin A1c  11.8

```