左连接的写法（Left join）.docVIP

左连接的写法（Left join） - left join If there are multiple tables, you can write in the following way Select count (*) From f_newpolicy_again a Left join t_cfg_l0_business_attr_value cfg1 On (substr (a.policy_attach_flg, 1, 2) = cfg1.attr_value_cn and Cfg1.attr_id = 277, and, cfg1.enable_flg =1) Left join t_cfg_l0_business_attr_value CFG2 On (a.holder_recognizee_rel = cfg2.attr_value_cn, and Cfg2.attr_id = 143, and, cfg2.enable_flg =1) Left join t_cfg_l0_business_attr_value cfg3 On (a.policy_method = cfg3.attr_value_cn, and, cfg3.attr_id = 276, and) Cfg3.enable_flg =1) Left join t_cfg_l0_business_attr_value cfg4 On (substr (a.holder_gender, 1, 1) = cfg4.attr_value_cn and Cfg4.attr_id = 161, and, cfg4.enable_flg =1) Left join t_cfg_l0_business_attr_value cfg5 On (a.sale_channel = cfg5.attr_value_cn, and, cfg5.attr_id = 295, and) Cfg5.enable_flg =1) Left join t_cfg_l0_business_attr_value cfg6 On (substr (a.recognizee_gender, 1, 1) = cfg6.attr_value_cn and Cfg6.attr_id = 161, and, cfg6.enable_flg =1) -- if its a form, you can write it like this Select count (*) From f_newpolicy_again a T_cfg_l0_business_attr_value cfg1 Where (substr (a.policy_attach_flg, 1, 2) = cfg1.attr_value_cn (+) and Cfg1.attr_id = 277, and, cfg1.enable_flg =1); Description, object, owner, object, name, cost, Cardinality, bytes, MB Describes the object owner object name and spends base bytes SELECT, STATEMENT, GOAL = ALL_ROWS, 11465743457924, 3.297733307 HASH, JOIN, RIGHT, OUTER, 11465743457924, 3.297733307 TABLE, ACCESS, BY, INDEX, ROWID, CCFRAME, T_CFG_L0_BUSINESS_ATTR_VALUE, 292430.000231743 INDEX RANGE SCAN CCFRAME R0_ATTR_VAL_MAP_FK 190 HASH, JOIN, RIGHT, OUTER, 11165743280426, 3.128458023 TABLE, ACCESS, BY, INDEX, ROWID, CCFRAME, T_CFG_L0_BUSINESS_ATTR_VALUE, 292430.000231743 INDEX RANGE SCAN CCFRAME R0_ATTR_VAL_MAP_FK 190 HASH, JOIN, RIGHT, OUTER, 10865743102928, 2.959182739 TABLE, ACCESS, BY, INDEX, ROWID, CCFRAME, T_CFG_L0_BUSINESS_ATTR_VALUE, 292430.000231743 INDEX RANGE SCAN CCFRAME R0_ATTR_VA