Unexpect Query results returned.....why?

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Enthusiast

Unexpect Query results returned.....why?

A typo resulted in this query. Even then the results were unexpected(by me anyway)
As show below I created a query with a sub select.
the subselect was invalid because the column selected in it did not exisit on the table from the subselect.
It did however exist on the First table.

I would have expected the query to fail, Instead it returned 606.
It appears the 3 nulls in the column not selected from the first table may have impacted the result. Any ideas?

BTEQ 12.00.00.00 Wed Aug 11 14:24:59 2010

+---------+---------+---------+---------+---------+---------+---------+----
/********************************************************************
sel * from dbc.dbcinfo;
RELEASE 12.00.03.02

sel count(*) from location.clstr_attrbt;

*** Query completed. One row found. One column returned.
*** Total elapsed time was 1 second.

Count(*)
-----------
609

+---------+---------+---------+---------+---------+---------+---------+----

sel count(*) from etl_work_perm.bv_loc_hier_crnt_rlgn where dma <> 'discont
inued';
*** Failure 5628 Column dma not found in etl_work_perm.bv_loc_hier_crnt_rlg
n.
Statement# 1, Info =0
*** Total elapsed time was 1 second.

+---------+---------+---------+---------+---------+---------+---------+----

sel count(*) from location.clstr_attrbt where
loc_id in (sel loc_id from etl_work_perm.bv_loc_hier_crnt_rlgn where dma <
> 'discontinued');

*** Query completed. One row found. One column returned.
*** Total elapsed time was 1 second.

Count(*)
-----------
606

+---------+---------+---------+---------+---------+---------+---------+----

Sel count(*) from location.clstr_attrbt where dma is null;

*** Query completed. One row found. One column returned.
*** Total elapsed time was 1 second.

Count(*)
-----------
3

+---------+---------+---------+---------+---------+---------+---------+----

Show table location.clstr_attrbt;

*** Text of DDL statement returned.
*** Total elapsed time was 1 second.

---------------------------------------------------------------------------
CREATE SET TABLE location.clstr_attrbt ,NO FALLBACK ,
NO BEFORE JOURNAL,
NO AFTER JOURNAL,
CHECKSUM = DEFAULT
(
Loc_id SMALLINT,
Rgn CHAR(5) CHARACTER SET LATIN NOT CASESPECIFIC,
Dma VARCHAR(50) CHARACTER SET LATIN NOT CASESPECIFIC,
Prim_Clstr VARCHAR(50) CHARACTER SET LATIN NOT CASESPECIFIC,
Prim_Clstr_Attrbt VARCHAR(100) CHARACTER SET LATIN NOT CASESPECIFIC,

Secd_Clstr VARCHAR(100) CHARACTER SET LATIN NOT CASESPECIFIC,
Secd_Clstr_Attrbt VARCHAR(100) CHARACTER SET LATIN NOT CASESPECIFIC,

Thrd_Clstr_Attrbt VARCHAR(100) CHARACTER SET LATIN NOT CASESPECIFIC,

Kshr CHAR(3) CHARACTER SET LATIN NOT CASESPECIFIC)
UNIQUE PRIMARY INDEX ( Loc_id );

+---------+---------+---------+---------+---------+---------+---------+----
Show table etl_work_perm.bv_loc_hier_crnt_rlgn;

*** Text of DDL statement returned.
*** Total elapsed time was 1 second.

---------------------------------------------------------------------------
CREATE SET TABLE etl_work_perm.bv_loc_hier_crnt_rlgn ,NO FALLBACK ,
NO BEFORE JOURNAL,
NO AFTER JOURNAL,
CHECKSUM = DEFAULT
(
Loc_Id SMALLINT,
Prim_Dem_Clstr VARCHAR(50) CHARACTER SET LATIN NOT CASESPECIFIC,
Prim_Clstr_Attrbt VARCHAR(100) CHARACTER SET LATIN NOT CASESPECIFIC,

Secd_Dem_Clstr VARCHAR(100) CHARACTER SET LATIN NOT CASESPECIFIC,
Secd_Clstr_Attrbt VARCHAR(100) CHARACTER SET LATIN NOT CASESPECIFIC,

Thrd_Clstr_Attrbt VARCHAR(100) CHARACTER SET LATIN NOT CASESPECIFIC,

Corp_ID VARCHAR(4) CHARACTER SET UNICODE NOT CASESPECIFIC,
Corp_Nm VARCHAR(10) CHARACTER SET UNICODE NOT CASESPECIFIC,
Rgn_Id SMALLINT,
Rgn_Nm VARCHAR(50) CHARACTER SET LATIN NOT CASESPECIFIC,
Rom_Id SMALLINT,
Rom_Nm VARCHAR(50) CHARACTER SET LATIN NOT CASESPECIFIC,
Dstr_Mgr_Id SMALLINT,
Dstr_Mgr_Nm VARCHAR(50) CHARACTER SET LATIN NOT CASESPECIFIC,
Dma_Id SMALLINT,
Dma_Nm VARCHAR(50) CHARACTER SET LATIN NOT CASESPECIFIC,
Loc_Typ_Cd CHAR(1) CHARACTER SET LATIN NOT CASESPECIFIC,
Str_Addr_1_Txt VARCHAR(255) CHARACTER SET LATIN NOT CASESPECIFIC,
Str_Addr_2_Txt VARCHAR(255) CHARACTER SET LATIN NOT CASESPECIFIC,
Cty_Nm VARCHAR(50) CHARACTER SET LATIN NOT CASESPECIFIC,
St_Cd CHAR(2) CHARACTER SET LATIN NOT CASESPECIFIC,
Cntry_Cd CHAR(2) CHARACTER SET LATIN NOT CASESPECIFIC,
Pstl_Cd VARCHAR(10) CHARACTER SET LATIN NOT CASESPECIFIC,
Pstl_Ext_Cd VARCHAR(10) CHARACTER SET LATIN NOT CASESPECIFIC,
Cnty_Cd CHAR(5) CHARACTER SET LATIN NOT CASESPECIFIC,
Lat_Num DECIMAL(10,6),
Lon_Num DECIMAL(10,6),
Ph_Num VARCHAR(20) CHARACTER SET LATIN NOT CASESPECIFIC,
Mgr_Nm VARCHAR(50) CHARACTER SET LATIN NOT CASESPECIFIC,
Opn_Dt DATE FORMAT 'YY/MM/DD',
Cl_Dt DATE FORMAT 'YY/MM/DD',
Sq_Ftg_Amt INTEGER,
cntng_ops_ind CHAR(1) CHARACTER SET LATIN NOT CASESPECIFIC,
Bnr_Cd CHAR(1) CHARACTER SET LATIN NOT CASESPECIFIC)
PRIMARY INDEX ( Loc_Id );

+---------+---------+---------+---------+---------+---------+---------+----