On 4/20/15, Janke, Julian <julian.janke at capgemini.com> wrote: > 'EXPLAIN PRAGMA journal_mode=WAL' returns 2 rows > > 0: 0 Init 0 0 0 > 1: 1 Halt 0 0 0 >
You should get this: addr opcode p1 p2 p3 p4 p5 comment ---- ------------- ---- ---- ---- ------------- -- ------------- 0 Init 0 0 0 00 1 JournalMode 0 1 5 00 2 ResultRow 1 1 0 00 3 Halt 0 0 0 00 What does: "PRAGMA compile_options;" and "SELECT sqlite_source_id();" show? > Is it the result of what you expected? > > -----Original Message----- > From: sqlite-users-bounces at mailinglists.sqlite.org > [mailto:sqlite-users-bounces at mailinglists.sqlite.org] On Behalf Of Richard > Hipp > Sent: Freitag, 17. April 2015 16:59 > To: General Discussion of SQLite Database > Subject: Re: [sqlite] Problems with pragma journal_mode > > On 4/17/15, Janke, Julian <julian.janke at capgemini.com> wrote: >> Hello, >> Thanks for your reply. >> >> I changed my code again: >> >> 1) rc = sqlite3_open(dbPath, &db); --> SQLITE_OK >> 2) rc = sqlite3_exec(db, "DROP TABLE IF EXISTS nosuchtable;", >> testCallbackPrint, 0, &zErrMsg); >> 3) rc = sqlite3_prepare_v2(db, "PRAGMA journal_mode=WAL;", 24, &stmt, >> NULL); >> --> SQLITE_OK >> 4) rc = sqlite3_step(stmt); --> SQLITE_DONE > > I do not understand this. "PRAGMA journal_mode" should always give a return > value, even when it fails. sqlite3_step() should have returned SQLITE_ROW. > > Please try instead, "EXPLAIN PRAGMA journal_mode=WAL". Verify that you get > multiple rows of output in that case. > > >> 5) rc = sqlite3_exec(db, "DROP TABLE IF EXISTS nosuchtable;", >> testCallbackPrint, 0, &zErrMsg); >> 6) txt = sqlite3_column_text (stmt, 0); --> returns an empty string >> 7) rc = sqlite3_finalize(stmt); --> SQLITE_OK >> 8) rc = sqlite3_close(db); --> SQLITE_OK >> >> Repeated the same steps with >> >> 3) rc = sqlite3_prepare_v2(db, "PRAGMA journal_mode;", 24, &stmt, >> NULL); --> SQLITE_OK >> >> To my knowledge, at line 4 SQLITE_ROW instead of SQLITE_DONE should be >> returned. >> >> "These routines may only be called when the most recent call to >> sqlite3_step() has returned SQLITE_ROW and neither sqlite3_reset() nor >> sqlite3_finalize() have been called subsequently." >> >> It looks as if all PRAGMA instructions are completely ignored, since >> the query for the status of the JOURNAL_MODE returns no result. >> >> Is it possible that I have turned off PRAMAs by anything or something >> is missing, so PRAMAs can run? >> >> Thanks for your help >> >> >> -----Original Message----- >> From: sqlite-users-bounces at mailinglists.sqlite.org >> [mailto:sqlite-users-bounces at mailinglists.sqlite.org] On Behalf Of >> Simon Slavin >> Sent: Donnerstag, 16. April 2015 17:56 >> To: General Discussion of SQLite Database >> Subject: Re: [sqlite] Problems with pragma journal_mode >> >> >> On 16 Apr 2015, at 2:33pm, Janke, Julian <julian.janke at capgemini.com> >> wrote: >> >>> rc = sqlite3_step(stmt); >>> --> returns SQLITE_DONE >> >> After the above two lines, print the value returned by >> >> sqlite3_column_text(stmt, 0) >> >> I'm not good at C off the top of my head but I think it's something >> like >> >> ----------------- >> >> const unsigned char * theText; >> >> [...] >> >> rc = sqlite3_prepare_v2(db, "PRAGMA journal_mode=WAL;", 24, &stmt, >> NULL); >> >> rc = sqlite3_step(stmt); >> theText = sqlite3_column_text (stmt, 0); printf ("text returned: %s", >> theText); >> >> rc = sqlite3_finalize(stmt); >> >> ----------------- >> >> Hope if I got it wrong someone else will tell you. By the way, you >> can also check the values returned from sqlite3_finalize() and >> sqlite3_close() since they can tell you useful things if something went >> wrong. >> >> Simon. >> _______________________________________________ >> sqlite-users mailing list >> sqlite-users at mailinglists.sqlite.org >> http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users >> >> ________________________________ >> >> Firma: Capgemini Deutschland GmbH >> Aufsichtsratsvorsitzender: Antonio Schnieder ? Gesch?ftsf?hrer: Dr. >> Michael Schulte (Sprecher) ? Jost F?rster ? Dr. Peter Lempp ? Dr. >> Volkmar Varnhagen >> >> Amtsgericht Berlin-Charlottenburg, HRB 98814 This message contains >> information that may be privileged or confidential and is the property >> of the Capgemini Group. It is intended only for the person to whom it >> is addressed. If you are not the intended recipient, you are not >> authorized to read, print, retain, copy, disseminate, distribute, or >> use this message or any part thereof. If you receive this message in >> error, please notify the sender immediately and delete all copies of this >> message. >> _______________________________________________ >> sqlite-users mailing list >> sqlite-users at mailinglists.sqlite.org >> http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users >> > > > -- > D. Richard Hipp > drh at sqlite.org > _______________________________________________ > sqlite-users mailing list > sqlite-users at mailinglists.sqlite.org > http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users > This message contains information that may be privileged or confidential and > is the property of the Capgemini Group. It is intended only for the person > to whom it is addressed. If you are not the intended recipient, you are not > authorized to read, print, retain, copy, disseminate, distribute, or use > this message or any part thereof. If you receive this message in error, > please notify the sender immediately and delete all copies of this message. > _______________________________________________ > sqlite-users mailing list > sqlite-users at mailinglists.sqlite.org > http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users > -- D. Richard Hipp drh at sqlite.org
