mysql - 将 oracle 查询转换为 MySQL 查询

Question

我正在尝试将此查询从 Oracle 转换为 MySQL:

CREATE TABLE SCT_201301_UMLS_SYN 
AS SELECT DISTINCT A.SCUI "SNOMED_CODE", A.STR "SNOMED_DISPLAY_NAME"
   , B.STR "UMLS_SYNONYM" 
FROM MRCONSO A, MRCONSO_UMLS B 
WHERE A.SCUI IN (SELECT referencedComponentId 
                 FROM SnomedCTtoICD10) 
AND A.SAB='SNOMEDCT' 
AND A.SUPPRESS='N' 
AND A.TTY='PT' 
AND B.LAT='ENG' 
AND B.SUPPRESS='N' 
AND A.CUI=B.CUI

有什么想法可以做到这一点吗？

Answer 1

如果您使用的是旧版本的 MySQL，那么您可能会遇到 in 的性能问题。这是一个替代方案，它应该适用于 MySQL 和 Oracle:

CREATE TABLE SCT_201301_UMLS_SYN 
AS SELECT DISTINCT A.SCUI "SNOMED_CODE", A.STR "SNOMED_DISPLAY_NAME"
   , B.STR "UMLS_SYNONYM" 
FROM MRCONSO A join
     MRCONSO_UMLS B
     on A.CUI = B.CUI
WHERE exists (SELECT 1
              FROM SnomedCTtoICD10 s
              where s.referencedComponentId  = a.scui) 
AND A.SAB='SNOMEDCT' 
AND A.SUPPRESS='N' 
AND A.TTY='PT' 
AND B.LAT='ENG' 
AND B.SUPPRESS='N'