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  • oracle psql 相关

    1查看分区大小

    SELECT SEGMENT_NAME, PARTITION_NAME, BYTES / 1024 / 1024 USED_MB
      FROM DBA_SEGMENTS
     WHERE SEGMENT_NAME IN ('tableone',
                            'tabletwo')

    2 比较两表数据差异

     (select * from table1)

      minus

     (select * from table2)

    3 '123,456,789'需要作为in('123','456','789')来查询,但是正常的replace后得到的还是一个字符串,所以才去下面的多行的办法,

      不过限于sql长度,反倒不如代码处理后直接得到'123','456','789'合算

      select replace(regexp_substr('123,456,789','[^,]+',1,level),',',' ') c1
                   from dual
                   connect by level<=length('123,456,789')-length(replace('123,456,789',',',''))+1

    4 oracle 10g trim不起作用

      REGEXP_REPLACE(param, '\s*', '')

    5 按照坐标计算两点间距离

        earth_padius:=6378137.0;
      radLat1:=3.141592625*lat1/180.0;
      radLat2:=3.141592625*lat2/180.0;
      a:=radLat1 - radLat2;
      b:=3.141592625*lng1/180.0 - 3.141592625*lng2/180.0; 
      s:=2*Asin(Sqrt(power(sin(a / 2), 2) +cos(radLat1) * cos(radLat2) * power(sin(b / 2), 2)));
      s := s * earth_padius;
      s := Round(s * 10000) / 10000.0;
      return(s);

    6 根据表名获取列值函数

    create or replace function FUNC_GET_MAX_ETL_TIME(tb_name varchar2,last_etl_time varchar2) return timestamp is
    Result timestamp;
    V_SQL VARCHAR2(500);
    V_RES_DATE timestamp;
    begin
    if last_etl_time is null then
    V_SQL:='select max(etl_time) as max_etl_time from '||tb_name;
    else
    V_SQL:='select max(etl_time) as max_etl_time from '||tb_name||' where etl_time>=to_timestamp('''||last_etl_time||''',''yyyy-mm-dd hh24:mi:ss.ff'')';
    end if;
    EXECUTE IMMEDIATE v_sql into V_RES_DATE;
    Result:= V_RES_DATE;
    return(Result);
    end FUNC_GET_MAX_ETL_TIME;

    7 自增列:1建立sequence 2建立触发器

    create sequence SEQ_ETL_K_T_SCHEDULE
    minvalue 1
    maxvalue 99999999
    start with 67
    increment by 1
    cache 64
    cycle
    order;

    create or replace trigger TIG_ETL_K_T_SCHEDULE_SEQ
    before insert on etl_kettle_trans_schedule
    for each row
    declare
    -- local variables here
    begin
    select SEQ_ETL_K_T_SCHEDULE.NEXTVAL into:new.id from dual;
    end TIG_ETL_K_T_SCHEDULE_SEQ;

    8 merge 使用

    BEGIN
    merge into table_a t1
    using (select * from table_b) t2
    on (t1.product_id = t2.product_id)
    when matched then
    update
    set t1.VIDEO_ID = t2.VIDEO_ID,
    t1.DESCRIPTION = t2.DESCRIPTION
    when not matched then
    insert
    values
    (t2.PRODUCT_ID,
    t2.VIDEO_ID,);
    END;

    新建基于日志的物化视图

    create materialized view log on tbname with rowid,sequence(col1,col2) including new values

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  • 原文地址:https://www.cnblogs.com/ai464068163/p/3121330.html
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