[sqlite] Bug Report - Analyzer app
Hi there, I use the sqlite3_analyzer.exe app get some data about tables (It's very useful by the way - thanks.) The newest version downloaded some days ago gave me import errors for the produced file, so I tried loading it manually, and then got the SQL which follows for one of my small DB files. The Object names in the Values seem to be unquoted, which is causing the failure for me: /* Removed lots of non-importing stats above this line *** The entire text of this report can be sourced into any SQL database engine for further analysis. All of the text above is an SQL comment. The data used to generate this report follows: */ BEGIN; CREATE TABLE space_used( name clob,-- Name of a table or index in the database file tblname clob, -- Name of associated table is_index boolean, -- TRUE if it is an index, false for a table nentry int, -- Number of entries in the BTree leaf_entries int, -- Number of leaf entries payload int, -- Total amount of data stored in this table or index ovfl_payload int, -- Total amount of data stored on overflow pages ovfl_cnt int, -- Number of entries that use overflow mx_payload int, -- Maximum payload size int_pages int,-- Number of interior pages used leaf_pages int, -- Number of leaf pages used ovfl_pages int, -- Number of overflow pages used int_unused int, -- Number of unused bytes on interior pages leaf_unused int, -- Number of unused bytes on primary pages ovfl_unused int, -- Number of unused bytes on overflow pages gap_cnt int, -- Number of gaps in the page layout compressed_size int -- Total bytes stored on disk ); INSERT INTO space_used VALUES(sqlite_master,sqlite_master,0,14,12,2473,0,0,534,1,3,0,898,520,0,3,4096); INSERT INTO space_used VALUES(DBases,DBases,0,5,5,644,0,0,181,0,1,0,0,349,0,0,1024); INSERT INTO space_used VALUES(sqlite_autoindex_DBases_1,DBases,1,5,5,64,0,0,14,0,1,0,0,937,0,0,1024); INSERT INTO space_used VALUES(DBTables,DBTables,0,15,10,4458,0,0,923,1,6,0,977,1589,0,1,7168); INSERT INTO space_used VALUES(DBHistory,DBHistory,0,0,0,0,0,0,0,0,1,0,0,1016,0,0,1024); INSERT INTO space_used VALUES(DBSettings,DBSettings,0,7,7,266,0,0,98,0,1,0,0,715,0,0,1024); INSERT INTO space_used VALUES(sqlite_autoindex_DBSettings_1,DBSettings,1,7,7,139,0,0,24,0,1,0,0,856,0,0,1024); INSERT INTO space_used VALUES(Idx_DBases_DBName,DBases,1,5,5,64,0,0,14,0,1,0,0,937,0,0,1024); INSERT INTO space_used VALUES(Idx_DBTables_DBID,DBTables,1,10,10,145,0,0,22,0,1,0,0,841,0,0,1024); INSERT INTO space_used VALUES(Idx_DBHistory,DBHistory,1,0,0,0,0,0,0,0,1,0,0,1016,0,0,1024); COMMIT; --- Importing this gets the usual no such column: sqlite_master error, but it all works well if I go add quotes everywhere. If it is already fixed, or if there is something I'm doing wrong, kindly point me in the right direction. Thank you ___ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
Re: [sqlite] Database gets locked for other processes
I know well the qt sqlite to say, maybe you aren't destroing the QSqlQuery class or simple call finish function, and the statement is openned helding the lock! Enviado via iPhone Em 29/10/2013, às 10:51, Stephan Beal sgb...@googlemail.com escreveu: On Tue, Oct 29, 2013 at 1:52 PM, Martin free...@rakor-net.de wrote: The program is running on Windows7. ... The program runs parallel on multiple machines all sharing the same SQLite-Database-file. Connecting multiple clients over a network share is a sure-fire way to corrupt your database. See the bottom half of this page: http://www.sqlite.org/whentouse.html as well as any number of threads in this mailing list archives regarding this topic. -- - stephan beal http://wanderinghorse.net/home/stephan/ http://gplus.to/sgbeal Since tyranny's the only guaranteed byproduct of those who insist on a perfect world, freedom will have to do. -- Bigby Wolf ___ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users ___ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
[sqlite] Update and GROUP BY
All, I have this table: DROP TABLE T; CREATE TABLE T (N, V, G); INSERT INTO T VALUES('a', 1, 'x'); INSERT INTO T VALUES('b', 3, 'x'); INSERT INTO T VALUES('c', null, 'x'); INSERT INTO T VALUES('d', 80, 'y'); INSERT INTO T VALUES('e', null, 'y'); INSERT INTO T VALUES('f', 60, 'y'); INSERT INTO T VALUES('g', null, 'y'); INSERT INTO T VALUES('h', null, 'z'); INSERT INTO T VALUES('i', 111, 'z'); I would like to see where N='c', V as the average for the group (G) were this record belongs to (so 'x'). Thus where N='c' I would get 2, and where N='e' or 'g', it would be 70, and where N=h it would be 111. I have no clue how to write this UPDATE statement. Could someone help me out? thanks Gert ___ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
Re: [sqlite] Update and GROUP BY
On 11/2/2013 1:06 PM, Gert Van Assche wrote: All, I have this table: DROP TABLE T; CREATE TABLE T (N, V, G); INSERT INTO T VALUES('a', 1, 'x'); INSERT INTO T VALUES('b', 3, 'x'); INSERT INTO T VALUES('c', null, 'x'); INSERT INTO T VALUES('d', 80, 'y'); INSERT INTO T VALUES('e', null, 'y'); INSERT INTO T VALUES('f', 60, 'y'); INSERT INTO T VALUES('g', null, 'y'); INSERT INTO T VALUES('h', null, 'z'); INSERT INTO T VALUES('i', 111, 'z'); I would like to see where N='c', V as the average for the group (G) were this record belongs to (so 'x'). Thus where N='c' I would get 2, and where N='e' or 'g', it would be 70, and where N=h it would be 111. I'm not sure I quite follow, but something like this perhaps: update T set V = (select avg(V) from T t2 where T.G = t2.G) where V is null; -- Igor Tandetnik ___ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
Re: [sqlite] Update and GROUP BY
Can you write a SELECT which returns the data that you want? Can you write a WHERE clause which selects the records you wish to update? For example: update T set V = (select avg(t2.g) from t as t2 where t2.g=t.g) where V IS NULL; assuming you only want to update the value of V in rows where V IS NULL ... -Original Message- From: sqlite-users-boun...@sqlite.org [mailto:sqlite-users- boun...@sqlite.org] On Behalf Of Gert Van Assche Sent: Saturday, 2 November, 2013 11:07 To: sqlite-users Subject: [sqlite] Update and GROUP BY All, I have this table: DROP TABLE T; CREATE TABLE T (N, V, G); INSERT INTO T VALUES('a', 1, 'x'); INSERT INTO T VALUES('b', 3, 'x'); INSERT INTO T VALUES('c', null, 'x'); INSERT INTO T VALUES('d', 80, 'y'); INSERT INTO T VALUES('e', null, 'y'); INSERT INTO T VALUES('f', 60, 'y'); INSERT INTO T VALUES('g', null, 'y'); INSERT INTO T VALUES('h', null, 'z'); INSERT INTO T VALUES('i', 111, 'z'); I would like to see where N='c', V as the average for the group (G) were this record belongs to (so 'x'). Thus where N='c' I would get 2, and where N='e' or 'g', it would be 70, and where N=h it would be 111. I have no clue how to write this UPDATE statement. Could someone help me out? thanks Gert ___ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users ___ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
Re: [sqlite] Update and GROUP BY
Igor, that is exactly what I need. I also understand how it is done now. Thanks! gert 2013/11/2 Igor Tandetnik i...@tandetnik.org On 11/2/2013 1:06 PM, Gert Van Assche wrote: All, I have this table: DROP TABLE T; CREATE TABLE T (N, V, G); INSERT INTO T VALUES('a', 1, 'x'); INSERT INTO T VALUES('b', 3, 'x'); INSERT INTO T VALUES('c', null, 'x'); INSERT INTO T VALUES('d', 80, 'y'); INSERT INTO T VALUES('e', null, 'y'); INSERT INTO T VALUES('f', 60, 'y'); INSERT INTO T VALUES('g', null, 'y'); INSERT INTO T VALUES('h', null, 'z'); INSERT INTO T VALUES('i', 111, 'z'); I would like to see where N='c', V as the average for the group (G) were this record belongs to (so 'x'). Thus where N='c' I would get 2, and where N='e' or 'g', it would be 70, and where N=h it would be 111. I'm not sure I quite follow, but something like this perhaps: update T set V = (select avg(V) from T t2 where T.G = t2.G) where V is null; -- Igor Tandetnik ___ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users ___ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
Re: [sqlite] Update and GROUP BY
Keith, thanks for this. The statement Igor made is what I need. gert 2013/11/2 Keith Medcalf kmedc...@dessus.com Can you write a SELECT which returns the data that you want? Can you write a WHERE clause which selects the records you wish to update? For example: update T set V = (select avg(t2.g) from t as t2 where t2.g=t.g) where V IS NULL; assuming you only want to update the value of V in rows where V IS NULL ... -Original Message- From: sqlite-users-boun...@sqlite.org [mailto:sqlite-users- boun...@sqlite.org] On Behalf Of Gert Van Assche Sent: Saturday, 2 November, 2013 11:07 To: sqlite-users Subject: [sqlite] Update and GROUP BY All, I have this table: DROP TABLE T; CREATE TABLE T (N, V, G); INSERT INTO T VALUES('a', 1, 'x'); INSERT INTO T VALUES('b', 3, 'x'); INSERT INTO T VALUES('c', null, 'x'); INSERT INTO T VALUES('d', 80, 'y'); INSERT INTO T VALUES('e', null, 'y'); INSERT INTO T VALUES('f', 60, 'y'); INSERT INTO T VALUES('g', null, 'y'); INSERT INTO T VALUES('h', null, 'z'); INSERT INTO T VALUES('i', 111, 'z'); I would like to see where N='c', V as the average for the group (G) were this record belongs to (so 'x'). Thus where N='c' I would get 2, and where N='e' or 'g', it would be 70, and where N=h it would be 111. I have no clue how to write this UPDATE statement. Could someone help me out? thanks Gert ___ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users ___ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users ___ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
Re: [sqlite] Update and GROUP BY
Good question Gert. Good solution, Igor and I like Keith's formatting. I thought the list might be interested in some of the statistical issues involved in determining if this method of replacing null values is an appropriate method for your data analysis and alternatives that are available. The statistical term for replacing missing values (a type of null value) with a computed or selected value is imputation. This problem/solution presented on this list is an implementation of a type of mean imputation. The statistical language R, has an entire package devoted to imputation (although ironically, it doesn't have this exact method -- it calculates the mean of an entire column without grouping or performs a more complex analysis. Although that may be because R experts know a way to add the grouping.). http://cran.r-project.org/web/packages/imputation/imputation.pdf The Wikipedia article, Imputation (statistics) http://en.wikipedia.org/wiki/Imputation_(statistics) points out some of the tradeoffs involved: Another imputation technique involves replacing any missing value with the mean of that variable for all other cases [records], which has the benefit of not changing the sample mean for that variable. However, mean imputation attenuates any correlations involving the variable(s) that are imputed. This is because, in cases with imputation, there is guaranteed to be no relationship between the imputed variable and any other measured variables. Thus, mean imputation has some attractive properties for univariate analysis but becomes problematic for multivariate analysis. Regression imputation has the opposite problem of mean imputation. A regression model is estimated to predict observed values of a variable based on other variables, and that model is then used to impute values in cases where that variable is missing. In other words, available information for complete and incomplete cases is used to predict whether a value on a specific variable is missing or not. Fitted values from the regression model are then used to impute the missing values. The problem is that the imputed data do not have an error term included in their estimation, thus the estimates fit perfectly along the regression line without any residual variance. This causes relationships to be over identified and suggest greater precision in the imputed values than is warranted. The regression model predicts the most likely value of missing data but does not supply uncertainty about that value. There is a lot more in the Wikipedia article, but this seemed like the most relevant section. HTH, Jim Callahan On Sat, Nov 2, 2013 at 2:23 PM, Igor Tandetnik i...@tandetnik.org wrote: On 11/2/2013 1:06 PM, Gert Van Assche wrote: All, I have this table: DROP TABLE T; CREATE TABLE T (N, V, G); INSERT INTO T VALUES('a', 1, 'x'); INSERT INTO T VALUES('b', 3, 'x'); INSERT INTO T VALUES('c', null, 'x'); INSERT INTO T VALUES('d', 80, 'y'); INSERT INTO T VALUES('e', null, 'y'); INSERT INTO T VALUES('f', 60, 'y'); INSERT INTO T VALUES('g', null, 'y'); INSERT INTO T VALUES('h', null, 'z'); INSERT INTO T VALUES('i', 111, 'z'); I would like to see where N='c', V as the average for the group (G) were this record belongs to (so 'x'). Thus where N='c' I would get 2, and where N='e' or 'g', it would be 70, and where N=h it would be 111. I'm not sure I quite follow, but something like this perhaps: update T set V = (select avg(V) from T t2 where T.G = t2.G) where V is null; -- Igor Tandetnik ___ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users ___ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
Re: [sqlite] possible join bug/regression with sqlite-3.8.1
On Mon, Oct 28, 2013 at 9:44 PM, Richard Hipp d...@sqlite.org wrote: The fix for this problem has been checked in: http://www.sqlite.org/src/info/9aac4e588c This problem was actually introduced in 3.8.0 but it was unreachable until some additional enhancements were added in 3.8.1. So 3.8.1 didn't actually cause the bug, it merely exposed it. This is a rather obscure problem, so we do not (currently) intend to rush out a patch release. The trunk is stable and usable if anybody really needs a fix right away. Thank you, Richard. I compiled today's trunk and it seems to fix the problem. Regards, Ferdinand ___ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
Re: [sqlite] Second ORDER BY statement
On 11/2/2013 11:24 PM, SongbookDB wrote: I'm using the following query to first, display in asc order any records that have something in the language column, then any fields where the language column is an empty string (fyi I don't have nulls in this column). It works perfectly. I'd now like to order the Language = rows by another column, Artist, but cannot crack how to restructure the query to accommodate this. SELECT * FROM (SELECT * FROM table1 WHERE Language != COLLATE NOCASE ORDER BY Language COLLATE NOCASE) UNION ALL SELECT * FROM table1 WHERE Language = COLLATE NOCASE LIMIT 100 select * from table1 order by Language = '', Language collate nocase, Artist collate nocase; -- Igor Tandetnik ___ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
Re: [sqlite] Second ORDER BY statement
Not sure how if this is the way to reply, but thank you Igor. On Sun, Nov 3, 2013 at 3:16 PM, Igor Tandetnik i...@tandetnik.org wrote: On 11/2/2013 11:24 PM, SongbookDB wrote: I'm using the following query to first, display in asc order any records that have something in the language column, then any fields where the language column is an empty string (fyi I don't have nulls in this column). It works perfectly. I'd now like to order the Language = rows by another column, Artist, but cannot crack how to restructure the query to accommodate this. SELECT * FROM (SELECT * FROM table1 WHERE Language != COLLATE NOCASE ORDER BY Language COLLATE NOCASE) UNION ALL SELECT * FROM table1 WHERE Language = COLLATE NOCASE LIMIT 100 select * from table1 order by Language = '', Language collate nocase, Artist collate nocase; -- Igor Tandetnik ___ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users -- Shaun Thomson Owner - SongbookDB ___ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users