SELECT clause using IN ... very slow?

Question

Could you guys please review the following query to an Oracle DB and point out what's wrong:

SELECT t1.name FROM t1, t2 WHERE t1.id = t2.id AND t2.empno IN (1, 2, 3, …, 200)

Query statistics:

• Time taken: 10.53 seconds.

Indices:

• t2.empno is indexed.

• t1.id is indexed.

• t2.id is indexed.

Update

---

The above query was just a sample replica of the query i use. Here below in a more true form

Explain Plan

Query:

SELECT 
    PRODUCT_REPRESENTATION_SK 
FROM 
    Product_Representation pr 
    , Design_Object do
    , Files files  
    ,EPS_STATUS epsStatus 
    ,EPS_ERROR_CODES epsError
    ,VIEW_TYPE viewTable  
WHERE  
    pr.DESIGN_OBJECT_SK = do.DESIGN_OBJECT_SK 
    AND  pr.LAYER_NAME !='Layer 0' 
    AND  epsStatus.EPS_STATUS_SK = pr.EPS_STATUS  
    AND epsError.EPS_ERROR_CODE = pr.EPS_ERROR_CODE 
    AND viewTable.VIEW_TYPE_ID = pr.VIEW_TYPE_ID 
    AND  files.pim_id = do.PIM_ID 
    AND  do.DESIGN_OBJECT_ID IN
        (
147086,149924,140458,135068,145197,134774,141837,138568,141731,138772,143769,141739,149113,148809,141072,141732,143974,147076,143972,141078,141925,134643,139701,141729,147078,139120,137097,147072,138261,149700,149701,139127,147070,149702,136766,146829,135762,140155,148459,138061,138762.............................................  200 such numbers
        )

Indexed Colums:

pr.DESIGN_OBJECT_SK
do.DESIGN_OBJECT_SK
do.DESIGN_OBJECT_ID
files.pim_id

Table

---

TABLE "PIM"."DESIGN_OBJECT" 
(   
"DESIGN_OBJECT_SK" NUMBER(*,0) NOT NULL ENABLE, 
"PIM_ID" NUMBER(*,0) NOT NULL ENABLE, 
"DESIGN_OBJECT_TYPE_SK" NUMBER(*,0) NOT NULL ENABLE, 
"DESIGN_OBJECT_ID" VARCHAR2(40 BYTE) NOT NULL ENABLE, 
"DIVISION_CD" NUMBER(*,0), 
"STAT_IND" NUMBER(*,0) NOT NULL ENABLE, 
"STAT_CHNG_TMST" TIMESTAMP (6), 
"CRTD_BY" VARCHAR2(45 BYTE), 
"CRT_TMST" TIMESTAMP (6), 
"MDFD_BY" VARCHAR2(45 BYTE), 
"CHNG_TMST" TIMESTAMP (6), 
"UPDATE_CNT" NUMBER(*,0), 
"GENDER" VARCHAR2(1 BYTE), 

 PRIMARY KEY ("DESIGN_OBJECT_SK")
)
TABLESPACE "PIM"  ENABLE, 

FOREIGN KEY ("DESIGN_OBJECT_TYPE_SK")
    REFERENCES "PIM"."DESIGN_OBJECT_TYPE" ("DESIGN_OBJECT_TYPE_SK")
        ON DELETE CASCADE ENABLE, 

FOREIGN KEY ("PIM_ID")
    REFERENCES "PIM"."FILES" ("PIM_ID")
        ON DELETE CASCADE ENABLE

)

Table 2

---

CREATE TABLE "PIM"."PRODUCT_REPRESENTATION" 
(
"PRODUCT_REPRESENTATION_SK" NUMBER(*,0) NOT NULL ENABLE, 
"DESIGN_OBJECT_SK" NUMBER(*,0) NOT NULL ENABLE, 
"VIEW_TYPE_ID" NUMBER(*,0) NOT NULL ENABLE, 
"LAYER_NAME" VARCHAR2(255 BYTE), 
"STAT_IND" NUMBER(*,0) NOT NULL ENABLE, 
"STAT_CHNG_TMST" TIMESTAMP (6), 
"CRTD_BY" VARCHAR2(45 BYTE), 
"CRT_TMST" TIMESTAMP (6), 
"MDFD_BY" VARCHAR2(45 BYTE), 
"CHNG_TMST" TIMESTAMP (6), 
"UPDATE_CNT" NUMBER(*,0), 
"EPS_STATUS" VARCHAR2(30 BYTE) NOT NULL ENABLE, 
"EPS_GENERATED_TIME" TIMESTAMP (6), 
"EPS_ERROR_CODE" NUMBER, 
"EPS_ERROR_DETAILS" VARCHAR2(500 BYTE), 
"DEEPSERVER_ASSET_LAYER_ID" VARCHAR2(255 BYTE), 
"PRODUCT_REPRESENTATION_LOC" VARCHAR2(255 BYTE), 

 PRIMARY KEY ("PRODUCT_REPRESENTATION_SK")
)
TABLESPACE "PIM"  ENABLE, 

FOREIGN KEY ("DESIGN_OBJECT_SK")
    REFERENCES "PIM"."DESIGN_OBJECT" ("DESIGN_OBJECT_SK") 
        ON DELETE CASCADE ENABLE, 
FOREIGN KEY ("VIEW_TYPE_ID")
    REFERENCES "PIM"."VIEW_TYPE" ("VIEW_TYPE_ID")
        ON DELETE CASCADE ENABLE, 

CONSTRAINT "EPS_ERROR_CODE_FK"
FOREIGN KEY ("EPS_ERROR_CODE")
     REFERENCES "PIM"."EPS_ERROR_CODES" ("EPS_ERROR_CODE") 
        ON DELETE CASCADE ENABLE, 
CONSTRAINT "EPS_STATUS_FK" 
FOREIGN KEY ("EPS_STATUS")
    REFERENCES "PIM"."EPS_STATUS" ("EPS_STATUS_SK") 
        ON DELETE CASCADE ENABLE
) 

Answer 1

The first thing that is wrong is using implict join syntax. That is a SQL antipattern.

If you have a large list in the IN clause, have you tried putting them in a table instead and using a join?

What database? Have you looked at your explain plan or execution plan to see where the slowdown is?