在之前的版本中ecpg 中只能使用returning into 来给c 变量赋值，如下：

exec sql update t1 set c ='aa' where id = 2 returning c into :c_val;

为了兼容oracle pro*c 中return into 的用法，从24.1 开始， LightDB 也支持通过return into 来返回return 的值到c变量中。使用方式如下：

示例

#include <stdio.h>
#include <stdlib.h>
#include <string.h>static void
print_sqlca()
{fprintf(stderr, "==== sqlca ====\n");fprintf(stderr, "sqlcode: %ld\n", sqlca.sqlcode);fprintf(stderr, "sqlerrm.sqlerrml: %d\n", sqlca.sqlerrm.sqlerrml);fprintf(stderr, "sqlerrm.sqlerrmc: %s\n", sqlca.sqlerrm.sqlerrmc);fprintf(stderr, "sqlstate: %5s\n", sqlca.sqlstate);fprintf(stderr, "===============\n");
}int main() {exec sql begin declare section;char c_val[100] = {0};exec sql end declare section;ECPGdebug(1, stderr);EXEC SQL CONNECT TO tcp:postgresql://127.0.0.1:5432/test_o;EXEC SQL SET AUTOCOMMIT TO ON;EXEC SQL WHENEVER SQLWARNING SQLPRINT;EXEC SQL WHENEVER SQLERROR CALL print_sqlca();exec sql create table t1(id integer,t text,d1 numeric,d2 float8,c char(10));exec sql insert into t1 values(1, 'a', 1.0, 1, 'a'),(2, null, null, null, null),(4, 'd', 4.0, 4, 'd');exec sql update t1 set c ='aa' where id = 2 return c into :c_val;exec sql delete from t1 where id = 2 return c into :c_val;exec sql insert into t1 values(2,null, null,null,  'bb') return c into :c_val;exec sqlDo $$Beginupdate t1 set c ='aa' where id = 2 return c into :c_val;end;$$ Language plorasql;exec sqlDo $$Begindelete from t1 where id = 2 return c into :c_val;end;$$ Language plorasql;exec sqlDo $$Begininsert into t1 values(2,null, null,null,  'bb') return c into :c_val;end;$$ Language plorasql;EXEC SQL DROP table t1;exec sql disconnect;return 0;
}