/* Open up a cursor for loop, also selecting * the "p" function which will write rows to * t2 for every row fetched from t1. */ FOR crec IN (Select tcol, p(tcol) FROM t1) LOOP -- Break out of the loop immediately EXIT; END LOOP; END; / Select COUNT(*) FROM t2; 注意:%...
opencurs1forselectreplace(word,' ','') from spam_keyword; --在loop前打开游标并绑定好范围,query定义范围的时候就把空格都替换掉 <<loop1>> --标签 loop fetch curs1 into str; ifnot foundthenexit; endif; i:=0; --每一次游标完成赋值后就把i初始化为0 <<loop2>> loop i:=i+1; strreturn...
Because variable substitution is done on a bound cursor’s query, there are really two ways to pass values into the cursor: either with an explicit argument to OPEN, or implicitly by referencing a PL/pgSQL variable in the query. For example, another way to get the same effect as the cur...
就返回FALSE declare cursor cur_users is select * from ma_users; begin --如果没有打开游标就使用这个属性,就会报invalid_cursor异常 /* if cur_users%found then dbms_output.put_line('更新积分'); end if; */ for v in cur_users loop update ma_users t set t.user_point = 1000 where t.id...
c3 CURSOR FOR SELECT * FROM employees; rowvar employees%ROWTYPE; BEGIN OPEN c3; LOOP FETCH FROM c3 INTO rowvar; EXIT WHEN NOT FOUND; END LOOP; CLOSE c3; END$$; Example of MOVE a cursor without fetching data MOVErepositions a cursor without retrieving any data and wo...
A MOVE statement sets FOUND true if it successfully repositions the cursor, false otherwise. A FOR or FOREACH statement sets FOUND true if it iterates one or more times, else false. FOUND is set this way when the loop exits; inside the execution of the loop, FOUND is not modified by ...
视图触发器的创建分类 :(INSTEAD OF) (INSERT | UPDATE | DELETE) (FOR EACH ROW) (WHEN NEW.? and,or OLD.? ... other boolean express ...)(before | after) (INSERT | UPDATE | DELETE) (FOR EACH STATEMENT) (WHEN BOOLEAN express except NEW or OLD or columns) 分类...
UsingFOR LOOPmight be a relevant solution for this option. STATIC Cursor will make a temporary copy of the data. For small data sets temporary tables can be created and declare a cursor that will select these tables. KEYSET Determining that membership and order ...
Under the covers, the library calls the PostgreSQL cursor operations with the pseudo-code: SET cursor_tuple_fraction TO 1.0; DECLARE cursor_1 CURSOR WITH HOLD FOR select * from widgets; loop rows = FETCH 100 FROM cursor_1; rows.each {|row| yield row} until rows.size < 100; CLOSE curso...
QueryEnvironment *queryEnv; /* 查询的执行环境;environment for query */ /* Features/options */ PortalStrategy strategy; /* 场景;see above */ int cursorOptions; /* DECLARE CURSOR选项位;DECLARE CURSOR option bits */ bool run_once; /* 是否只执行一次;portal will only be run once */ ...