Snowflake中的动态SQL优化

在Snowflake中运行动态SQL时，我遇到了以下错误:

未完成对‘SQL_Main’的赋值，因为值超出了变量的大小限制.其大小为263；限制为256(以字节为单位的内部存储大小).

以下是代码:

SET v_G = '1';
SET v_G1 = $v_G::VARCHAR;
SET v_P = (SELECT "txtstr" FROM table2 WHERE "grouping" = $v_G);
SET SQL_MAIN = 'CREATE TABLE N_1 AS
                SELECT a1.YEARMONTH as "DATE",
                COUNT(a1.RECORD_NUM) AS "COUNT",
                ' || $v_G1 ||' AS "GROUP"
                FROM table1 a1
                WHERE ' || $v_P || ' GROUP BY YEARMONTH';

EXECUTE IMMEDIATE $SQL_MAIN;

set d_max_row = (select count(*) from table2");

begin
    let counter :=1;
        while (counter <= $d_max_row)
        do
            SET v_G = $v_G+1;
            SET v_G1 = $v_G::VARCHAR;
            SET v_P = (SELECT "txtstr" FROM table2 WHERE "grouping" = $v_G);
            SET SQL_MAIN = 'INSERT INTO N_1 (DATE, COUNT, GROUP)
                            SELECT a1.YEARMONTH as "DATE",
                            COUNT(a1.RECORD_NUM) AS "COUNT",
                            ' || $v_G1 ||' AS "GROUP"
                            FROM table1 a1
                            WHERE ' || $v_P || ' GROUP BY YEARMONTH';

            EXECUTE IMMEDIATE $SQL_MAIN;
           
            counter := counter + 1;
        end while;
    return counter;
end;

作为表1中的条件，有没有办法遍历表2中"txtstr"列中的每条记录，并在单独的表中返回结果？

我找到了很多针对Java脚本的示例，但没有针对SQL的太具体的示例.请让我知道这是否可能在snowflake.

谢谢!