sql 数据操作片段

Posted 2021-05-13

--  Regex replace
UPDATE TABLE T SET T.FIELD = REGEXP_REPLACE (T.FIELD, 'Search', 'Replace')

--  Update based on another table
UPDATE COMPOUND_INVENTORY t
SET T.PUBCHEM_CID = (
SELECT C.PUBCHEM_CID
FROM COMPOUND C
WHERE T.CID = C.CID)

--  Check for missing against another table
SELECT L.CID 
FROM COMPOUND L 
LEFT JOIN COMPOUND_INVENTORY I ON L.CID = I.CID
WHERE I.CID IS NULL

--  Count repeats
SELECT   col,
         COUNT(dupe_col) AS dupe_cnt
FROM     TABLE
GROUP BY col
HAVING   COUNT(dupe_col) > 1
ORDER BY COUNT(dupe_col) DESC

--  Select row range
SELECT *
FROM (SELECT T1.*, ROWNUM AS ROWNUMBER
FROM COMPONENT_LIBRARY T1)
WHERE ROWNUMBER BETWEEN 10 AND 18

-- Create database link 
CREATE DATABASE LINK UADEVORADB
  CONNECT TO user IDENTIFIED BY password 
  USING '(DESCRIPTION=
  (ADDRESS=(PROTOCOL=TCP)(HOST=uadevorahost1)(PORT=1521))
  (CONNECT_DATA=(SERVICE_NAME=uadevoradb.domaindb)))'