数据库的clob字段存储json串 ，比如 {"PS-SB_PSNL":"450","PS-SB_PSXL":"85","PS-SB_GL":"250"}
定义2个函数，使用函数解析表中的存储json值的字段
使用fn_parsejson(json值,'key')获得值
CREATE OR REPLACE FUNCTION fn_split(p_str IN VARCHAR2,
p_delimiter IN VARCHAR2)
RETURN ty_tbl_str_split IS
j INT := 0;
i INT := 1;
len INT := 0;
len1 INT := 0;
str VARCHAR2(4000);
str_split ty_tbl_str_split := ty_tbl_str_split();
BEGIN
len := LENGTH(p_str);
len1 := LENGTH(p_delimiter);
WHILE j < len LOOP
j := INSTR(p_str, p_delimiter, i);
IF j = 0 THEN
j := len;
str := SUBSTR(p_str, i);
str_split.EXTEND;
str_split(str_split.COUNT) := ty_row_str_split(strValue => str);
IF i >= len THEN
EXIT;
END IF;
ELSE
str := SUBSTR(p_str, i, j - i);
i := j + len1;
str_split.EXTEND;
str_split(str_split.COUNT) := ty_row_str_split(strValue => str);
END IF;
END LOOP;
RETURN str_split;
END fn_split;
CREATE OR REPLACE FUNCTION fn_parsejson(p_jsonstr varchar2,
p_key varchar2) RETURN VARCHAR2
IS
rtnVal VARCHAR2(200);
i NUMBER(2);
jsonkey VARCHAR2(200);
jsonvalue VARCHAR2(200);
json VARCHAR2(1000);
BEGIN
IF p_jsonstr IS NOT NULL THEN
json := REPLACE(p_jsonstr,'{','') ;
json := REPLACE(json,'}','') ;
json := replace(json,'"','') ;
FOR temprow IN(SELECT strvalue AS VALUE FROM TABLE(fn_split(json, ','))) LOOP
IF temprow.VALUE IS NOT NULL THEN
i := 0;
jsonkey := '';
jsonvalue := '';
FOR tem2 IN(SELECT strvalue AS VALUE FROM TABLE(fn_split(temprow.value, ':'))) LOOP
IF i = 0 THEN
jsonkey := tem2.VALUE;
END IF;
IF i = 1 THEN
jsonvalue := tem2.VALUE;
END IF;
i := i + 1;
END LOOP;
IF(jsonkey = p_key) THEN
rtnVal := unistr(REPLACE(jsonvalue,'\u','\'));
END if;
END IF;
END LOOP;
END IF;
RETURN rtnVal;
END fn_parsejson;