Problems w/compound SQL statement

From: Kevin Lloyd <kevinl_at_centrelab.com>
Date: 1998/03/03
Message-ID: <6di6hb$j98$1@ns2.naccess.net>#1/1

Below is an example of a compound SQL statement that returns 0 rows (Example #3) when using tables "QCLINK" and "SAMPHEADER".

Each individual SQL query returns at least one row (Examples 1 &2).

Also below, is an example of a compound SQL statement that returns 1 row (Example #4) when using tables "SAMPHEADER" and "SAMPDATA".

---

My questions is this: can anyone think of a reason why the compound select statement using the qclink table won't work ???

---

1. Individual SQL statement #1

SQL> SELECT SAMP_JOINID FROM SAMPHEADER WHERE SAMP_JOINID='SJ322977'; SAMP_JOINID

---

SJ322977

2) Individual SQL statement #2

SQL> SELECT SAMP_JOINID FROM QCLINK WHERE SAMP_JOINID='SJ322977'; SAMP_JOINID

---

SJ322977
SJ322977
SJ322977
SJ322977
SJ322977

3) Compound SQL Statement using QCLINK in ()

SQL> SELECT SAMP_JOINID FROM SAMPHEADER WHERE SAMP_JOINID IN   2 (SELECT SAMP_JOINID FROM QCLINK WHERE SAMP_JOINID='SJ322977'); no rows selected

4) Compound SQL Statement using SAMPDATA in ()

SQL> SELECT SAMP_JOINID FROM SAMPHEADER WHERE SAMP_JOINID IN   2* (SELECT SAMP_JOINID FROM SAMPDATA WHERE SAMP_JOINID='SJ322977') SAMP_JOINID

---

SJ322977 Received on Tue Mar 03 1998 - 00:00:00 CST