Re: [sqlite] Student's t-test table
Thanks Simon, I know how to perform the importation. However thanks of the idea. I start looking for it. On Sun, Nov 16, 2014 at 8:46 AM, Simon Slavin wrote: > > On 16 Nov 2014, at 7:39am, Giuseppe Costanzi > wrote: > >> do you know if a database exists in sqlite with the values, degrees of >> fredom vs probability (alfa) of the t Student? > > If you can find one in text or .csv format, we can tell you how to import it. > > Simon. > ___ > 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] Student's t-test table
On 16 Nov 2014, at 7:39am, Giuseppe Costanzi wrote: > do you know if a database exists in sqlite with the values, degrees of > fredom vs probability (alfa) of the t Student? If you can find one in text or .csv format, we can tell you how to import it. Simon. ___ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
[sqlite] Student's t-test table
Hi to everybody, do you know if a database exists in sqlite with the values, degrees of fredom vs probability (alfa) of the t Student? I need it to calculate confidence intervals to compare two means regards bc1966 ___ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
Re: [sqlite] Discrepancy with indexing and WHERE clause with AND/OR
On 2014/11/14 16:32, RP McMurphy wrote: On Tue, 11/11/14, RP McMurphy wrote: > If you can provide any examples where ANALYZE makes a query slower, I suspect the developer team would like > to see them. > After we run analyze and then let the process run for a while the DB contents change - and it can change quite considerably depending upon what is happening. I suspect that the analyze data gets stale, but I don't know how to track such things in sqlite. Anyhow we can't keep running analyze every few minutes because it takes a long time to run with our DB and it appears to block all other actions until it is done. Firstly, that is a considerably different problem to your initial claim that ANALYZE makes queries slower. That said, it is an understandable concern. When you say the data changes, does the shape actually change? Because all that matters to analyze is the shape of the data, not the data itself. As an example, consider the following three small tables: A: ID, No, Name, Value, XT, AX 1, 1, John, 34,Panthera Leo,2014-11-12 09:44:26 2, 2, Chris, 88,Panthera Pardis, 2014-11-13 04:17:43 3, 3, Martin, 20, etc... B: ID, No, Name, Value, XT, AX 1, 1, John, 34,, 2, X1, John, , Panthera Leo, 3, A1, John, , , 2014-11-12 09:44:26 4, 2, Chris, 88,, 5, X2, Chris, , Panthera Pardis, 6, A2, Chris, , , 2014-11-13 04:17:43 etc. C: ID, No, Name, Value, XT, AX 106, 62, Andrew, 18,Loxodonta Africana, -00-00 00:00:00 107, 677,James,12,Podocarpus Falcatus, 2014-11-09 14:27:12 108, 176612, Flemming, 40,Tectonia Grandis,2014-11-14 03:31:55 etc. From table A to B the data did not change significantly, but the shape of it changed significantly in respect of cardinality, value types, fill rate etc. From A to C the data is completely different, but the shape is exactly the same. Running Analyze for table A which shape-shifts into B over time (which is highly unlikely) will certainly see the values become "stale". Running Analyze for A which eventually changes into C (very likely) will have minimal effect on the outcome of the Analyze data and hence on the outcome of the Query Planner decisions. To re-iterate the question posed earlier - If you can show that the QP makes a worse decision after analyzing a table - OR - that the decision degrades over time for a table of which the shape does not change effectively - I am sure the case would be considered as undesirable and the devs would probably be interested in doing something about it. Other options include forcing the use of an Index or Indices (see "USING" in the SQLite SQL docs) or using cross-joins and the like. A this point we are considering writing VDBE code directly and bypassing the parser. Has anyone else done this? Is it going to be a huge ugly can-of-worms if we do that? Not just a can of worms - an insane one, and what is worse, you will immediately lose any benefit of periodic updates and all the other advances in technology so frequently visited upon SQLite because your version is no longer interchangeable with the new ones. Further to that, this speaks of the willingness to take 3 steps in the wrong direction to avoid one step in the right direction - maybe some past experience influence or some other unknowns which are not immediately obvious now is influencing this thought? (I only ask because this is not uncommon). If you do have a table of which the shape keeps changing to the point it needs re-analyzing every few minutes, then you are working with the worst DB in history and should really make your own native storage solution - but I am 90% certain this is not the case and you are simply overlooking something or not doing something efficiently - which we will be glad to help with if you post schemata and maybe link an example DB or such. Unlike me, some other people on here are extremely knowledgeable on SQL and specifically the inner workings of SQLite - Tell us the full story, we might save you hundreds of hours. ___ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
Re: [sqlite] Discrepancy with indexing and WHERE clause with AND/OR
On 14 Nov 2014, at 2:32pm, RP McMurphy wrote: > After we run analyze and then > let the process run for a while the DB > contents change - and it can change quite > considerably depending > upon what is > happening > > I suspect that the analyze data gets stale, but > I don't know how to track such things in > sqlite. Anyhow we can't keep running > analyze every few minutes because it takes a > long time to run with our DB > and it appears > to block all other actions until it is done. Okay. ANALYZE isn't used for specific information about every piece of data. It's used to evaluate the 'chunkiness' of each column and index. For instance one column may only ever have two values in it -- "yes" or "no" -- whereas another column may have a different value in it for each row. So unless the character of your data changes, if you run ANALYZE once when you have realistic data, you shouldn't need to run it again even if your tables grow to 100 times their original size. You don't need to run ANALYZE under normal operation. Perhaps once a year in a yearly maintenance run or something. Or if you create a new index so SQLite can see how useful that index will be for certain operations. As others have shown you using EXPLAIN QUERY PLAN, SQLite is itself capable of doing the expansion you describe to get an efficient query. I would definitely not recommend you try beating the SQLite internals which have been developed and improved for years. It's going to be more effective to see if you can spot some point at which your query starts executing slowly. Simon. ___ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
Re: [sqlite] querying with BLOB in WHERE clause, possible?
On Fri, Nov 14, 2014 at 3:57 PM, bjdodo wrote: > I've got it now. E.g. for delete you can do this: > A minor fix: the 'try' needs to be moved to... > > int argidx = 0; > SQLiteStatement statement = mDB.compileStatement(sql); > here. Because... > throw new RuntimeException("unexpected argument type); > if that happens then you're not closing it. > try { > return statement.executeUpdateDelete(); > } finally { > statement.close(); > } > -- - stephan beal http://wanderinghorse.net/home/stephan/ http://gplus.to/sgbeal "Freedom is sloppy. But 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
Re: [sqlite] querying with BLOB in WHERE clause, possible?
I've got it now. E.g. for delete you can do this: String sql = "DELETE FROM " + table + (!TextUtils.isEmpty(whereClause) ? " WHERE " + whereClause : ""); int argidx = 0; SQLiteStatement statement = mDB.compileStatement(sql); if (whereArgs != null) { for (WhereArg wa : whereArgs) { Object o = wa.getParamValueRaw(); if (o == null) { statement.bindNull(++argidx); } else if (o instanceof String) { statement.bindString(++argidx, (String) o); } else if (o instanceof Long) { statement.bindLong(++argidx, (Long) o); } else if (o instanceof Double) { statement.bindDouble(++argidx, (Double) o); } else if (o instanceof byte[]) { statement.bindBlob(++argidx, (byte[]) o); } else { throw new RuntimeException("unexpected argument type); } } } try { return statement.executeUpdateDelete(); } finally { statement.close(); } -- View this message in context: http://sqlite.1065341.n5.nabble.com/querying-with-BLOB-in-WHERE-clause-possible-tp44550p79220.html Sent from the SQLite mailing list archive at Nabble.com. ___ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
Re: [sqlite] Missing SQLite.Designer.SQLiteDataViewSupport?
I have installed the version 1.0.94.0 and I get the same problem, telling me "Could not find Any Appropriate resources for the culture or the Specified neutral culture. Make sure" SQLite.Designer.SQLiteDataViewSupport2012.xml "was embedded or linked into Correctly assembly "SQLite.Designer" at compile time, or all the satellite assemblies That required are loadable and fully signed. " What could it be? -- View this message in context: http://sqlite.1065341.n5.nabble.com/Missing-SQLite-Designer-SQLiteDataViewSupport-tp78087p79225.html Sent from the SQLite mailing list archive at Nabble.com. ___ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
Re: [sqlite] Discrepancy with indexing and WHERE clause with AND/OR
I am resending this message below from 3 days ago because it never made it to the list. RP PS: Messages seem to take a long time to go through the gmane system, at least half a day and sometimes more in my experience so far. On Tue, 11/11/14, RP McMurphy wrote: Subject: Re: Discrepancy with indexing and WHERE clause with AND/OR To: sqlite-users@sqlite.org Date: Tuesday, November 11, 2014, 6:31 PM > If you can provide any examples where ANALYZE makes a query slower, I suspect the developer team would like > to see them. > After we run analyze and then let the process run for a while the DB contents change - and it can change quite considerably depending upon what is happening. I suspect that the analyze data gets stale, but I don't know how to track such things in sqlite. Anyhow we can't keep running analyze every few minutes because it takes a long time to run with our DB and it appears to block all other actions until it is done. A this point we are considering writing VDBE code directly and bypassing the parser. Has anyone else done this? Is it going to be a huge ugly can-of-worms if we do that? RP ___ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users