1、代码如下:
void TestCache(otl_connect& otlConn) { try { char sql[1024] = {0}; sprintf(sql,"call test1(1)"); otl_stream stream(100, sql, otlConn,otl_implicit_select); int id; while(!stream.eof()) { stream>>id; char sql2[1024] = {0}; sprintf(sql2,"call test2(:Id<int>)"); otl_stream stream2(100, sql2, otlConn,otl_implicit_select); stream2<<id;
int ff =0;
while(!stream2.eof()) { stream2>>ff; } } } catch(otl_exception& ex) { printf("ExecuteSql Error, ErrorMsg[%s], Sql[%s]", ex.msg, ex.stm_text); } }
2、执行otl_stream stream2(100, sql2, otlConn,otl_implicit_select);的时候出错,如下:
Commands out of sync; you can't run this command now
特别注意:如果test1 只返回1条或者0条记录,不会导致这个异常。
3、错误原因:mysql上一次的查询没有将结果集释放掉,又进行下一次的查询。
4、otl:在第一个stream读取期间,第二个stream使用了绑定变量,会导致上面的问题,不知道otl内部是怎么封装的。
5、解决办法:
a、第二个stream不使用绑定变量,如下:
void TestCache(otl_connect& otlConn) { try { char sql[1024] = {0}; sprintf(sql,"call test1(1)"); otl_stream stream(100, sql, otlConn,otl_implicit_select); int id; while(!stream.eof()) { stream>>id; char sql2[1024] = {0}; sprintf(sql2,"call test2(%d)",id); otl_stream stream2(100, sql2, otlConn,otl_implicit_select); int ff =0;
while(!stream2.eof()) { stream2>>ff; } } } catch(otl_exception& ex) { printf("ExecuteSql Error, ErrorMsg[%s], Sql[%s]", ex.msg, ex.stm_text); } }
b、先把第一个stream读取完,再进行第二个stream,如下:
void TestCache(otl_connect& otlConn) { try { char sql[1024] = {0}; sprintf(sql,"call test1(1)"); otl_stream stream(100, sql, otlConn,otl_implicit_select); vector<int> intVec; int id; while(!stream.eof()) { stream>>id; intVec.push_back(id); } for(vector<int>::iterator iter = intVec.begin(); iter != intVec.end(); ++iter) { char sql2[1024] = {0}; sprintf(sql2,"call test2(:Id<int>)"); otl_stream stream2(100, sql2, otlConn,otl_implicit_select); stream2<<id; int ff =0;
while(!stream2.eof()) { stream>>ff; } } } catch(otl_exception& ex) { printf("ExecuteSql Error, ErrorMsg[%s], Sql[%s]", ex.msg, ex.stm_text); } }