Problem mit String Bau in plsql

Question

ich wie eine Zeichenfolge habe

LEAST("col1", "col2") GREATEST("col1", "col2") 

und aus dieser Zeichenfolge mag ich eine resultierende Zeichenfolge wie

col1 IN LEAST(v_col1, v_col2) AND col2 IN GREATEST(v_col1, v_col2) 

wo v_ den Spaltennamen angehängt wird und sie repräsentieren vordefinierte Variablen. Anzahl der Spalten kann dynamisch sein. Ich habe zu viele Optionen ausprobiert, aber ich kann nicht das gewünschte Ergebnis erzielen.

Bitte vorschlagen.

Dies sind einige Optionen, die ich versuche, aber scheint nicht in die richtige Richtung zu bewegen.

declare txt varchar2(1000); 
anstxt varchar2(1000); 
begin 
txt := 'LEAST("col1","col2")'; 
select REGEXP_SUBSTR(TXT,'"([^"]*)"',1,1,'',1) into anstxt from dual; 
DBMS_OUTPUT.PUT_LINE(anstxt); 
end; 


declare 
v_Var5 varchar2(50); 
v_Var6 varchar2(1000); 
v_Var7 varchar2(10); 
v_Var8 varchar2(10); 
CURSOR c3 IS 
    SELECT column_expression FROM all_ind_expressions WHERE table_owner = 'schemaname' AND table_name = 'mytable';  

names_t c3%ROWTYPE; 
    TYPE names_ntt IS TABLE OF names_t%TYPE; -- must use type 
    l_names names_ntt; 
BEGIN 
v_Var7 := ' IN ('; 
v_Var8 := ');'; 
--FOR i in c3 
OPEN c3; 
    FETCH c3 BULK COLLECT INTO l_names; 
    CLOSE c3; 

    FOR indx IN 1..l_names.COUNT LOOP 
    IF(l_names.COUNT > 1) THEN 
     v_Var6 := v_Var6 || REPLACE(l_names(indx).column_expression, '"', ''); 
     DBMS_OUTPUT.PUT_LINE(l_names(indx).column_expression); 
    ELSE 
     v_Var6 := REPLACE(l_names(indx).column_expression, '"', ''); 
    END IF; 
    END LOOP; 
    v_Var6 := v_Var7 || REPLACE(v_Var6, ' ', ' AND ') || v_Var8; 
--DBMS_OUTPUT.PUT_LINE(v_Var5); 
DBMS_OUTPUT.PUT_LINE(v_Var6); 
END; 

Grüße.

Answer 1

Nach so vielen Versuchen habe ich endlich, was ich gesucht habe. Ich teile dies für die Referenz des Forums.

DECLARE 
v_Var5 varchar2(1000); 
v_Var6 varchar2(1000); 
v_Var7 varchar2(10); 
v_Var8 varchar2(10); 
v_Var9 varchar2(1000); 
v_Counter NUMBER; 
CURSOR c3 IS 
    SELECT column_expression FROM all_ind_expressions WHERE table_owner = 'myschema' AND table_name = 'mytable';  

names_t c3%ROWTYPE; 
    TYPE names_ntt IS TABLE OF names_t%TYPE; -- must use type 
    l_names names_ntt; 
BEGIN 
    v_Counter := 1; 
    v_Var7 := ' IN ('; 
    v_Var8 := ');'; 

    OPEN c3; 
    FETCH c3 BULK COLLECT INTO l_names; 
    CLOSE c3; 

    FOR indx IN 1..l_names.COUNT 
    LOOP 
    --v_Counter := l_names.COUNT; 
    IF(l_names.COUNT > 1) THEN 
     v_Var6 := REPLACE(l_names(indx).column_expression, '"', ''); 
     FOR i IN 1..l_names.COUNT LOOP 
     v_Var6 := REPLACE(v_Var6, REGEXP_SUBSTR(l_names(i).column_expression,'"([^"]*)"',1,i,'',1),'v_' || REGEXP_SUBSTR(l_names(i).column_expression,'"([^"]*)"',1,i,'',1)); 
     END LOOP; 
     v_Var9 := REGEXP_SUBSTR(l_names(indx).column_expression,'"([^"]*)"',1,indx,'',1) || ' IN ('; 
     CASE 
     WHEN indx < l_names.COUNT THEN 
      v_Var5 := v_Var5 || v_Var9 || v_Var6 || ') AND '; 
     WHEN indx = l_names.COUNT THEN 
      v_Var5 := v_Var5 || v_Var9 || v_Var6 || ');'; 
     END CASE; 
    ELSE 
     v_Var6 := REPLACE(l_names(indx).column_expression, '"', ''); 
     v_Var6 := REPLACE(v_Var6, REGEXP_SUBSTR(l_names(indx).column_expression,'"([^"]*)"',1,indx,'',1),'v_' || REGEXP_SUBSTR(l_names(indx).column_expression,'"([^"]*)"',1,indx,'',1)); 
     v_Var9 := REGEXP_SUBSTR(l_names(indx).column_expression,'"([^"]*)"',1,indx,'',1) || ' IN '; 
     v_Var5 := v_Var5 || v_Var9 || v_Var6; 
    END IF; 
    END LOOP; 
    --DBMS_OUTPUT.PUT_LINE('v_Var9' || CHR(13) || v_Var9); 
    --DBMS_OUTPUT.PUT_LINE('v_Var6' || CHR(13) ||v_Var6); 
    DBMS_OUTPUT.PUT_LINE('v_Var5' || CHR(13) ||v_Var5); 
END;