根据一个表更新另外一表的数据

 

 

 

根据一个表的数据来更新另外一表的数据：

 

Oralce和DB2：

 

UPDATE A
 SET (A1, A2, A3) = (SELECT B1, B2, B3 FROM B WHERE A.ID = B.ID)

 

UPDATE A
    SET (A1, A2, A3) = (SELECT B1, B2, B3 FROM B WHERE A.ID = B.ID)
    WHERE ID IN (SELECT B.ID FROM B WHERE A.ID = B.ID)

 

---------------------------------------------------------------------------------------------

MS SQL Server：

 

UPDATE A
    SET A1 = B1, A2 = B2, A3 = B3
    FROM A LEFT JOIN B ON A.ID = B.ID

UPDATE A
    SET A1 = B1, A2 = B2, A3 = B3
    FROM A, B WHERE A.ID = B.ID

 

 

 

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另今天写一脚本，没技术含量，已改进，记录一笔：

 

 #------------------------------------
#  GetDate for each day.
#------------------------------------

k=0

while [ $k -lt 12 ]
do

i=0
let k=$k+1

case $k in
         1|3|5|7|8|10|12)
                 j=31;;
         4|6|9|11)
                 j=30 ;;
         2)
                 j=28;;
         *)
                 echo fuck！;;
esac

if [ $k -lt 10 ]; then
         k=0$k
fi

        while [ $i -lt $j ]
        do

            let i=$i+1

            if [ $i -lt 10 ]; then
            {
                #sqlplus pos/pos @bhml 2010060$i
                echo 2010${k}0$i
            }
            else
            {
                #sqlplus pos/pos @bhml 201006$i
                echo 2010$k$i
            }
            fi
        done
done