Need help to tune queries
SELECT OBL.ORDER_BASE_GID OB_GID, MAX(DECODE(RQ.OB_LINE_REFNUM_QUAL_XID,'UK
CATEGORY',SUBSTR(OBLR.OB_LINE_REFNUM_VALUE, INSTR(OBLR.OB_LINE_REFNUM_VALUE,
'|')+1))) UK_LEVEL1, MAX(DECODE(RQ.OB_LINE_REFNUM_QUAL_XID,'UK DIVISION',
SUBSTR(OBLR.OB_LINE_REFNUM_VALUE, INSTR(OBLR.OB_LINE_REFNUM_VALUE,'|')+1)))
UK_LEVEL2, MAX(DECODE(RQ.OB_LINE_REFNUM_QUAL_XID,'UK DEPARTMENT',
SUBSTR(OBLR.OB_LINE_REFNUM_VALUE, INSTR(OBLR.OB_LINE_REFNUM_VALUE,'|')+1)))
UK_LEVEL3, MAX(DECODE(RQ.OB_LINE_REFNUM_QUAL_XID,'UK SUB DEPARTMENT',
SUBSTR(OBLR.OB_LINE_REFNUM_VALUE, INSTR(OBLR.OB_LINE_REFNUM_VALUE,'|')+1)))
'|')+1))) UK_LEVEL1, MAX(DECODE(RQ.OB_LINE_REFNUM_QUAL_XID,'UK DIVISION',
SUBSTR(OBLR.OB_LINE_REFNUM_VALUE, INSTR(OBLR.OB_LINE_REFNUM_VALUE,'|')+1)))
UK_LEVEL2, MAX(DECODE(RQ.OB_LINE_REFNUM_QUAL_XID,'UK DEPARTMENT',
SUBSTR(OBLR.OB_LINE_REFNUM_VALUE, INSTR(OBLR.OB_LINE_REFNUM_VALUE,'|')+1)))
UK_LEVEL3, MAX(DECODE(RQ.OB_LINE_REFNUM_QUAL_XID,'UK SUB DEPARTMENT',
SUBSTR(OBLR.OB_LINE_REFNUM_VALUE, INSTR(OBLR.OB_LINE_REFNUM_VALUE,'|')+1)))
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