c - CREATE and DROP a table while another statement is in place -


in previous implementation, streaming results sqlite3 table directly output application. however, since changing interface temporary data structure, need number of rows. preferred way seems temporary table, original 

sprintf(query,"select %s x, avg(%s) y, avg((%s)*(%s)) ysq %s %s=%s , %s group x;",x,y,y,y,from,across,val,where); sqlite3_prepare_v2(db, query, -1, &acresult,null); while(sqlite3_step(acresult)==sqlite_row) { ... } sqlite3_finalize(acresult);

turns into

sprintf(query,"create temp table tt select %s x, avg(%s) y, avg((%s)*(%s)) ysq %s %s=%s , %s group x;",x,y,y,y,from,across,val,where); sqlite3_prepare_v2(db, query, -1, &acresult,null); sqlite3_step(acresult); sqlite3_finalize(acresult);  sqlite3_prepare_v2(db, "select count(*) tt;", -1, &acresult, null); sqlite3_step(acresult); int length = sqlite3_column_int(acresult,0); sqlite3_finalize(acresult);  sqlite3_prepare_v2(db, "select x,y, ysq tt;", -1, &acresult, null); while(sqlite3_step(acresult)==sqlite_row) { ... } sqlite3_finalize(acresult); sqlite3_prepare_v2(db, "drop table tt;", -1, &acresult, null); sqlite3_step(acresult); sqlite3_finalize(acresult);

now, works. problem have inside loop across stepping query, seems responsible table being locked when try drop it. if finalize query, "works" (the drop works; else breaks because it's part of logic). there no possible way outer query referencing tt, because created within "scope".

is there way of reminding sqlite shouldn't locked, or stuck switching outer loop away streaming well?

this read-only application (with exception of temp table), if helps.


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