语句块定义
decalre -- 变量声明 var1 number(2); -- 仅声明 var2 char(2) := ‘11‘; -- 在声明的同时初始化 begin -- 语句 end; -- 语句块结束
if 语句
if a = 1 or b = 2 then elsif c = 3 then else end if;
case 语句
case语句如果作为分支控制语句，最后结束语句是end case，如果是作为select语句里的控制语句则只需要end。
declare num number(10) := 1; begin case when num = 0 then dbms_output.put_line( ‘zero‘); when num = 1 then dbms_output.put_line( ‘one‘); else dbms_output.put_line( ‘default‘); end case; case num when 0 then dbms_output.put_line( ‘zero‘); when 1 then dbms_output.put_line( ‘one‘); else dbms_output.put_line( ‘default‘); end case; end;
for 循环
- 循环一个范围
格式：for i in [start .. end] loop ... end loop;
for i in 0..9 loop dbms_output.put_line(‘i:‘ || i); end loop;
- 遍历隐式游标
隐式游标的好处是不需要手动关闭，方便。
for currow in ( select t.col1, t.col2 from tableName t where ... ) loop if currow.col1 = 0 then return; -- 中止sp，返回 end if; end loop;
while 循环
isok := 9; while isok >= 0 loop isok := isok - 1; if isok = 8 then continue; -- 与编程语言的 continue 语义一样，跳过当前循环的剩余语句，回到循环开始 end if; if isok = 4 then exit; -- 与编程语言的 break 语义一样，跳出循环 end if; dbms_output.put_line(‘isok:‘ || isok); end loop; dbms_output.put_line(‘outside while loop .‘);
cursor
隐式游标
for currow in ( select t.col1, t.col2 from tableName t where ... ) loop if currow.col1 = 0 then return; -- 中止sp，返回 end if; end loop;
显式游标
declare isok integer; v_event_id number(10); v_isagain number(2); v_rate number(2); v_sender char(11) := ‘13800138000‘; cursor cursorVar is select event_id, isagain, rate from call_event where sender = v_sender; -- 声明游标 begin open cursorVar; -- 打开游标 loop fetch cursorVar into v_event_id, v_isagain, v_rate; -- 取值 exit when cursorVar%notfound; --当没有记录时退出循环 dbms_output.put_line(v_event_id || ‘, ‘ || v_isagain || ‘, ‘ || v_rate); end loop; close cursorVar; -- 关闭游标 --游标的属性有：%FOUND,%NOTFOUNRD,%ISOPEN,%ROWCOUNT; --%FOUND:已检索到记录时，返回true --%NOTFOUNRD：检索不到记录时，返回true --%ISOPEN:游标已打开时返回true --%ROWCOUNT:代表检索的记录数，从1开始 end;
带参数游标
declare isok integer; v_event_id number(10); v_isagain number(2); v_rate number(2); v_sender char(11) := ‘13800138000‘; cursor cursorVar(p_sender varchar2) is select event_id, isagain, rate from call_event where sender = p_sender; -- 声明游标 begin open cursorVar(v_sender); -- 打开游标，在括号里传参。 loop fetch cursorVar into v_event_id, v_isagain, v_rate; -- 取值 exit when cursorVar%notfound; --当没有记录时退出循环 dbms_output.put_line(v_event_id || ‘, ‘ || v_isagain || ‘, ‘ || v_rate); end loop; close cursorVar; -- 关闭游标 end;
存储过程
create or replace procedure sp_name ( -- 入参、出参列表， 逗号分隔。 uid in varchar2, -- 不能带长度信息 startDate in date , -- 第二个输入参数 defaultVar in varchar2 default "", -- 默认参数，如果不传，要注意参数的顺序 isok out number , -- 输出参数 result out varchar2 -- 第二个输出参数 ) as -- 变量声明，每个声明用分号结束。可以在声明的同时初始化 var1 varchar2( 11); var2 number( 2) := 123 ; begin -- 字符串拼接用 || dbms_output.put_line( ‘isok:‘ || ‘abc‘ ); -- 调用其他存储过程 sub_sp_name(param1, prarm2, outParam1, outParam2); end; -- 存储过程结束
函数
create or replace function func ( -- 入参、出参列表， 逗号分隔。 uid in varchar2, -- 不能带长度信息 startDate in date , -- 第二个输入参数 defaultVar in varchar2 default "", -- 默认参数，如果不传，要注意参数的顺序 isok out number , -- 输出参数 result out varchar2 -- 第二个输出参数 ) return number -- 定义返回类型 as -- 变量声明，每个声明用分号结束。可以在声明的同时初始化 var1 varchar2( 11); var2 number( 2) := 123 ; begin -- 字符串拼接用 || dbms_output.put_line( ‘isok:‘ || ‘abc‘ ); return ret_val; end;
存储过程与函数的异同
- 两者定义类似，都可以带输入输出参数。
- 函数有返回值，存储过程没有。
- 函数的调用要在select语句里；而存储过程不用，可以独立调用。
一些管理语句
查看最近执行的sql
select * from v$sql order by FIRST_LOAD_TIME desc
查看正在执行的sql
SELECT B.SID, B.STATUS, B.OSUSER, B.TERMINAL, B.PROGRAM, B.MACHINE, B.SQL_EXEC_START AS "SQL STARTTIME", A.SQL_ID, A.SQLTYPE, A.SQL_TEXT, A.LAST_ACTIVE_TIME AS "SQL ENDSTIME" -- 语句执行完成前，一直在变 FROM V$SQL A, V$SESSION B WHERE A.SQL_ID = B.SQL_ID AND B.STATUS = ‘ACTIVE‘ AND B.SID <> (SELECT SID FROM V$MYSTAT WHERE ROWNUM <= 1) AND B.SID > 1 ;
查看sql语句的执行进度：
SELECT A.SID AS "进程SID", OPNAME AS "执行操作", TARGET AS "操作对象", START_TIME AS "开始时间", (SYSDATE - START_TIME) * 24 * 60 * 60 AS "已耗时(秒)", TIME_REMAINING AS "剩余时间", A.USERNAME AS "用户名称", MACHINE AS "主机", TERMINAL AS "终端", PROGRAM AS "进程", STATE AS "当前状态", ROUND( SOFAR/TOTALWORK*100,2 ) AS "完成百分比" FROM GV$SESSION_LONGOPS A, GV$SESSION B WHERE A.TIME_REMAINING>0 AND A.SID=B.SID AND B.SERIAL#=A.SERIAL# AND A.INST_ID=B.INST_ID AND TARGET NOT LIKE ‘SYS%‘;
查看表空间的情况：
SELECT TABLESPACE_NAME AS "表空间名称", BLOCK_SIZE AS "块大小(db_block_size)", STATUS AS "当前状态", DECODE(A.CONTENTS, ‘PERMANENT‘, ‘永久表空间‘, ‘TEMPORARY‘, ‘临时表空间‘, ‘UNDO‘, ‘回退表空间‘) AS "表空间类型", SEGMENT_SPACE_MANAGEMENT AS "空间管理方式", ROUND(DECODE(A.CONTENTS, ‘PERMANENT‘, (SELECT SUM(USER_BYTES) AS "SIZE_BYTE" FROM DBA_DATA_FILES B WHERE B.TABLESPACE_NAME = A.TABLESPACE_NAME), ‘TEMPORARY‘, (SELECT SUM(USER_BYTES) FROM DBA_TEMP_FILES C WHERE C.TABLESPACE_NAME = A.TABLESPACE_NAME), ‘UNDO‘, (SELECT SUM(USER_BYTES) AS "SIZE_BYTE" FROM DBA_DATA_FILES D WHERE D.TABLESPACE_NAME = A.TABLESPACE_NAME)) / 1024 / 1024 / 1024) AS "分配空间(GB)", ROUND(DECODE(A.CONTENTS, ‘PERMANENT‘, (SELECT SUM(BYTES) FROM DBA_SEGMENTS H WHERE H.TABLESPACE_NAME = A.TABLESPACE_NAME), ‘TEMPORARY‘, (SELECT ALLOCATED_SPACE FROM DBA_TEMP_FREE_SPACE F WHERE F.TABLESPACE_NAME = A.TABLESPACE_NAME), ‘UNDO‘, (SELECT SUM(BYTES) FROM DBA_UNDO_EXTENTS J WHERE J.STATUS IN (‘ACTIVE‘, ‘UNEXPIRED‘) AND J.TABLESPACE_NAME = A.TABLESPACE_NAME)) / 1024 / 1024 / 1024) AS "已用空间(GB)", ROUND(DECODE(A.CONTENTS, ‘PERMANENT‘, (SELECT SUM(BYTES) FROM DBA_FREE_SPACE E WHERE E.TABLESPACE_NAME = A.TABLESPACE_NAME), ‘TEMPORARY‘, (SELECT FREE_SPACE FROM DBA_TEMP_FREE_SPACE F WHERE F.TABLESPACE_NAME = A.TABLESPACE_NAME), ‘UNDO‘, (SELECT SUM(BYTES) FROM DBA_FREE_SPACE G WHERE G.TABLESPACE_NAME = A.TABLESPACE_NAME)) / 1024 / 1024 / 1024) AS "可用空间(GB)" FROM DBA_TABLESPACES A WHERE A.TABLESPACE_NAME LIKE ‘RDC%‘ OR A.TABLESPACE_NAME LIKE ‘UNDO%‘ ORDER BY CONTENTS, TABLESPACE_NAME;
时间： 2024-11-09 18:52:13