For the sake of the argument, let's try to devise a workable scheme for such an
undertaking:
Lets assume you have a 32-bit "real rowid" and four 8-bit "value" fields.
How to distribute these in the 64-bit rowid?
Rrid low = MSB | v1 | v2 | v3 | v4 | r1r2r3r4 | LSB or
Rrid high = MSB | r1r2r3r4
Simple answer: Don't!
This sounds like a misguided attempt to save space in the disk image by messing
around with the rowid of a table (which is what "integer primary key" declares
the column to be an alias of).
Whatever you stuff in there needs to be unique and, if you intend to use
foreign k
Your experiments are not reproducible unless you provide at least an indication
of the schema.
Most probably, something you have not yet considered/revealed makes using the
index to look up a irrelevant. Maybe a is declared as "integer primary key",
making it an alias of the rowid.
-Ursprü
An index is only usable for that subset of a queries' equality constraints that
forms a leading subset of the fields handled by the index.
E.g.if you are looking at equality constraints for fields a, b and c in one
query, then you need an index whose first three fields are a, b and c (in any
o
The sqlite char() function returns unicode. Apparently, the encoding for code
point 133 is two characters, namely c2 85. You seem to be expecting char() to
return ISO characters, which it does not do.
Calling sqlite3_value_text16 instructs SQLite to convert the contents of the
field into utf16
It would be so much easier if you could provide hex dumps of the strings
involved. Maybe just a few characters and a verbal description of what you
think you are storing (greek lowercase alpha, ...).
From appearances it seems that your text objects are locale aware, which would
suggest a code-p
Von: sqlite-users [mailto:sqlite-users-boun...@mailinglists.sqlite.org] Im
Auftrag von Lars Frederiksen
Gesendet: Montag, 07. August 2017 09:00
An: 'SQLite mailing list'
Betreff: Re: [sqlite] TEXT shows as (WIDEMEMO) in DBGrid
...
But I also realized that it is not possible just to put some gree
A "temp table" would only be visible in the session that creates it and would
not live past the end of the session. Sequences should be persistent...
-Ursprüngliche Nachricht-
Von: sqlite-users [mailto:sqlite-users-boun...@mailinglists.sqlite.org] Im
Auftrag von Nico Williams
Gesendet: F
>Von: sqlite-users [mailto:sqlite-users-boun...@mailinglists.sqlite.org] Im
>Auftrag von Nico Williams
>
>On Tue, Aug 01, 2017 at 10:56:47AM -0700, Matt Chambers wrote:
>> load_extension() has the very sensible behavior of:
>> > So for example, if "samplelib" cannot be loaded, then names like
>> >
A sequence is very easily implemented as a virtual table that keeps the current
values in a separate table my_sequences (name text primary key, initial
integer, current integer, increment integer).
CREATE VIRTUAL TABLE seq_1 USING sequence ([[,]]); --
defaults 1, 1
The xCreate/xConnect functio
Naming conventions (if strictly adhered to) are moderately good at avoiding
conflicts, but take the guesswork out of "faking a pointer". It also assumes
that pointers for "whatever" are interchangeable between different queries in a
process, i.e. passing a "whatever" pointer from statement A to
You should NOT be relying on column names UNLESS you set them yourself.
-Ursprüngliche Nachricht-
Von: sqlite-users [mailto:sqlite-users-boun...@mailinglists.sqlite.org] Im
Auftrag von petern
Gesendet: Samstag, 08. Juli 2017 21:37
An: SQLite mailing list
Betreff: [sqlite] VALUES clause q
We are using a shared memory segment (created during application startup) to
contain the data records, but you could also use a memory mapped file. This
will keep the static data identical across all connections and processes.
When writing your VT module, consider giving it a readonly/readwrite
Double quotes is specifically for building identifiers that "look strange"
(i.e. embedded spaces, keywords, ...) which IMHO should be avoided because it
tends to clutter up the statement.
Single quotes is for building strings.
Integer is a keyword, "integer" is an identifier and 'integer' a str
CP1252 = Windows-1252 = ISO 8859-1 aka Latin-1, an extension of ASCII
-Ursprüngliche Nachricht-
Von: sqlite-users [mailto:sqlite-users-boun...@mailinglists.sqlite.org] Im
Auftrag von Gilles
Gesendet: Montag, 19. Juni 2017 16:23
An: SQLite Maillist
Betreff: Re: [sqlite] How to search for
Limit2 is taken to be the alias of table foo.
-Ursprüngliche Nachricht-
Von: sqlite-users [mailto:sqlite-users-boun...@mailinglists.sqlite.org] Im
Auftrag von Robert Cousins
Gesendet: Sonntag, 18. Juni 2017 21:19
An: sqlite-users@mailinglists.sqlite.org
Betreff: [sqlite] unusual but trivi
What do the following statements return, when run in sqlite3.exe (Please note
that single quotes are SQLite3 string delimiters):
SELECT hex('Île-de-France');
SELECT hex(region) FROM MyTable WHERE LIBREG like '%le-de-France' LIMIT 1;
I expect one of them is ISO (lead character > 7F) and the othe
I have found it much simpler and more robust to write a CSV virtual table to
handle the formatting.
e.g.
CREATE VIRTUAL TABLE csv_input USING csv ( );
Opens the named file, reads the first line and interprets the contents as a
list of field names. You can then
INSERT INTO SELECT FROM csv_
"many (sometimes several thousand) statments" sounds like it could be heavy on
memory requirements.
Are you inserting one row per statement or all rows in one statement? The
latter would be really hard on memory because SQLite will have to parse the
whole statement and generate a gigantic SQL p
Try
Create index t2.idx on link (...)
Which is what the syntax diagram would recommend. If you ask SQLite to create
an index in t2, it will figure out that the table needs to be in t2 too.
-Ursprüngliche Nachricht-
Von: sqlite-users [mailto:sqlite-users-boun...@mailinglists.sqlite.org]
Looking at the generated program for mulit-tuple INSERT INTO ... VALUE yields
the following structure:
Only 1 tuple (standard case)
2 tuples
Each further tuple adds a segment (1 opcode per field + data)
and a yield opcode to the generated VDBE program, and an equivalent amount t
Just like any other join, but with tables in the desired order and the word
CROSS added
SELECT ... FROM CROSS JOIN ...
-Ursprüngliche Nachricht-
Von: sqlite-users [mailto:sqlite-users-boun...@mailinglists.sqlite.org] Im
Auftrag von Thomas Flemming
Gesendet: Dienstag, 30. Mai 2017 18:1
INTEGER and LONG can both store 64 bits in SQlite. The difference is that
"INTEGER PRIMARY KEY" makes the column an alias for the rowid, whereas "LONG
PRIMARY KEY" defines a second, possibly redundant index.
-Ursprüngliche Nachricht-
Von: sqlite-users [mailto:sqlite-users-boun...@mailing
If you stuff all 18MB of your data into a single INSERT, then SQlite will need
to generate a single program that contains all 18MB of your data (plus code to
build rows aout of that). This will put a heavy strain on memory requirements
and offset any speed you hope to gain.
The SOP is to put ma
The expression is calculated as given in each case. The difference being that a
constant constraint is recognized in the query planner (and thus calculated
once with the result being saved), whereas a constant expression as a return
value is not.
-Ursprüngliche Nachricht-
Von: sqlite-us
Try for yourself.
.mode explain
explain select 2 +2;
explain select 4;
BTW: The "from Tbl" clause will only affect the number of result rows (1 for
every row in Tbl).
-Ursprüngliche Nachricht-
Von: sqlite-users [mailto:sqlite-users-boun...@mailinglists.sqlite.org] Im
Auftrag von xTom B
There is no "underscore notation" for multiword constraints. "NOT_NULL" is not
"NOT NULL" and "PRIMARY KEY" is not "PRIMARY_KEY". As long as whatever you
provide can be split up into tokens in a way that matches the grammar there
will be no syntax error. It will just not be matching what you thi
The number 1 references the first column of the result set, 2 the second, and 3
is an error because there are only 2 columns.
If the expression is a constant, then there is only 1 group.
You are missing any meaningful information because you do not have an aggregate
expression in your select li
The trick is to have a way to identify the first/current row and use that in
the WHERE clause.
e.g. SELECT ... FROM customers WHERE customer_id >= last_displayed LIMIT
window_size
If your select statement is a complex join without any usable key, you will
have to resort to storing the results
I. Is there
something that can be done with the DB handle after calling one of the _prepare
or _step functions which reveals the query cost already calculated by SQLite?
On Mon, May 22, 2017 at 1:35 AM, Hick Gunter wrote:
> SQLite will determine the set of constraints that are possible agai
SQLite will determine the set of constraints that are possible against yout
virtual table from the query you are preparing. It will then call your
xBestIndex function a number of times with different subsets of the constraints
marked aus "usable". Your xBestIndex function needs to return (among
This is well documented. The result of expressions involving strings with
embedded NUL characters is undefined. The conversion BLOB -> TEXT will check
for and stop at the first embedded NUL; in none occurs, a terminating NUL is
added. You may store any sequence of bytes in a BLOB, but please do
SQLite is a library, not a server. There is no automatic backup. You can copy
the .db file when the application is inactive, or have the application call the
SQLite backup API to perform the backup whenever it feels the urge to do so.
-Ursprüngliche Nachricht-
Von: sqlite-users [mailto:s
Maybe Prakash Premkumar or Sairam Gaddam
, who seemed hell bent on implementing stored
procedures (or at least storing generated bytecode) about two years ago, have
made progress in the meantime?
-Ursprüngliche Nachricht-
Von: sqlite-users [mailto:sqlite-users-boun...@mailinglists.sqli
on sqlite shell output…
On 18 April 2017 at 16:28, Hick Gunter wrote:
> Richard Hipp wrote:
> >I think the OP is referring to a problem that comes up because the
> >field
> width and precision of a printf() format are measured in bytes, not
> characters, and if the input is m
>On 4/18/17, Hick Gunter wrote:
>> I don't see any calls to sqlite3() functions in your "isolated test case".
>> Maybe you are having problems with character encoding outside of sqlite?
>
>I think the OP is referring to a problem that comes up because the fie
I don't see any calls to sqlite3() functions in your "isolated test case".
Maybe you are having problems with character encoding outside of sqlite?
-Ursprüngliche Nachricht-
Von: sqlite-users [mailto:sqlite-users-boun...@mailinglists.sqlite.org] Im
Auftrag von aotto
Gesendet: Montag, 17.
A TVF is just a "calling convention" for abbreviating a specific SELECT on a
virtual table. It implies neither mutability of the returned values, nor
persistence beyond the scope of the statement. Indeed the carray() example you
give later is an eponymous ephemeral table, i.e. it does not requir
My guess ist hat random() is being called once for each expression containing
Y. Using constant values from a regular table works as expected. It is exactly
the bytecode output by EXPLAIN that could help to determine what
happens, but unfortunately you did not post it.
asql> insert into t valu
The SQLITE_INDEX_SCAN_UNIQUE flag is a hint for the query planner. It does not
affect query execution mechanics. You should be returning TRUE from xEOF after
the first call to your xNext function (provided indeed that there is only 1 row
that matches the value). Or you need to add a LIMIT 1 clau
ot;d" (in my example, the "b" I gave was 1).
R Smith's approach does the trick nicely!
Thanks,
Hamish
On 3 April 2017 at 10:48, Hick Gunter wrote:
> I am not sure I correctly understand what you want.
>
> This is the value of d associated with a randomly chosen recor
I am not sure I correctly understand what you want.
This is the value of d associated with a randomly chosen record from the group
of records having the highest value of a tha also fulfills b == 1;
SELECT MAX(a),d FROM x WHERE b=1;
If you want the value of d within each group of records sharin
The Close (1) in the second program is closing (=deleting) the ephemeral table.
I have no idea if this would also be handled in Halt or not.
-Ursprüngliche Nachricht-
Von: sqlite-users [mailto:sqlite-users-boun...@mailinglists.sqlite.org] Im
Auftrag von Cezary H. Noweta
Gesendet: Mittwoc
Nachricht-
Von: sqlite-users [mailto:sqlite-users-boun...@mailinglists.sqlite.org] Im
Auftrag von Bob Friesenhahn
Gesendet: Mittwoch, 29. März 2017 17:05
An: SQLite mailing list
Betreff: Re: [sqlite] VT table behavior change between 3.10 and 3.17
On Wed, 29 Mar 2017, Hick Gunter wrote:
>
2017, Hick Gunter wrote:
>
> To avoid anomalies when changing "key fields", SQLite will scan through the
> whole cursor first, saving the rowids and new contents of the record(s)
> satisfying the WHERE clause. It will then close the cursor and call xUpdate
> for the a
> [...] Why xOpen-ed cursor cannot be used to write to a table?
> The xUpdate method alone is used to perform updates to virtual tables.
> It does not take a cursor argument.
> Also, there is no method taking a cursor argument that allows data to be
> changed.
> The documentation is correct in
:48, Hick Gunter wrote:
> According to the documentation of Virtual Tables and Opcodes:
> [...]
> xOpen( table, cursor) is called to announce that SQLite intends to
> read from a table. A cursor cannot be used to write to a table. Do
> whatever is necessary to read from the backing st
According to the documentation of Virtual Tables and Opcodes:
xBegin( table ) is called to announce that SQlite intends to write to the
table. There is no cursor involved. Do whatever is necessary to write to the
backing store and set any VT implementation specific information in the table
stru
The section at the end, which is executed first, contains the necessary
database locking and schema checking opcodes. These cannot be generated before
the rest of the program has analysed which operations are performed on which
tables and therefore which of the attached database(s) needs to be l
Ignore the first note. Table main.t is persistent, whrereas temp.t is
automatically dropped on closing the connection.
-Ursprüngliche Nachricht-
Von: sqlite-users [mailto:sqlite-users-boun...@mailinglists.sqlite.org] Im
Auftrag von Hick Gunter
Gesendet: Mittwoch, 29. März 2017 08:40
An
I find the .explain/explain functionality very helpful in clearing up
what happens and why.
Note the error when creating main.t.
Note the database number 1 (for temp) vs. 0 (for main) in the OpenWrite and
TableLock instructions.
asql> create temp table t (db, val);
asql> create table main.t (d
Can you provide an example of the bytecode produced?
In the SQLite shell type:
.explain
explain ;
Typical output (with SQLite version 3.7.14.1):
asql> .explain
asql> explain update mytable set myfield=2 where myconst=7;
addr opcode p1p2p3p4 p5 comment
---
] Im
Auftrag von Max Vlasov
Gesendet: Dienstag, 28. März 2017 13:37
An: SQLite mailing list
Betreff: Re: [sqlite] All versions compatible "very big" estimatedCost (Virtual
tables)
On Tue, Mar 28, 2017 at 12:51 PM, Dominique Devienne
wrote:
> On Tue, Mar 28, 2017 at 11:00 AM, Hick
>FWIW, I've often wondered about the cost estimates of real tables versus
>virtual tables, especially since many vtables implementations don't involve
>real IO but pure in-memory computations. There's >very little advice or
>documentation on this important subject, and Max's email reveals that
>-Ursprüngliche Nachricht-
>em...@n0code.net wrote:
>> I’ve scoured the archives and the sqlite documentation but can’t find
>> the definitive rules for defining table and column names.
>
>Everything is allowed, except names beginning with "sqlite_".
>
This calls for a (not quite) OT Quote
Hey, neat idea! To expand on my previous post:
CREATE TRIGGER wakeup AFTER INSERT ON cmd BEGIN SELECT
cond_broadcast('cmd_ready'); END;
-Ursprüngliche Nachricht-
Von: sqlite-users [mailto:sqlite-users-boun...@mailinglists.sqlite.org] Im
Auftrag von Richard Damon
Gesendet: Sonntag, 26. M
I think this kind of problem (transfer of information between cooperating
processes) is best solved using the tools designed for inter-process
communication and not attempting to abuse a DB system designed to isolate
processes from unfinished changes.
Have the processes share a condition variab
If I Interpret your text correctly, you are claiming that your
mpxMalloc/mpxRealloc is issuing the same address twice, without mpxFree being
called in between?
Are you tracking mpxRealloc calls correctly? If the area pointed to is not
large enough, a new area will be allocated, the data copied
rag von Richard Hipp
Gesendet: Donnerstag, 23. März 2017 12:06
An: SQLite mailing list
Betreff: [sqlite] Still running 3.7.x. Was: RIGHT JOIN! still not supported?
On 3/23/17, Hick Gunter wrote:
> I am still runnning SQLIte
> 3.7.14.1
Why?
3.17.0 is backwards compatible, fixes obscure bugs,
After some thinking I came up with this:
First, set up the example (note: no CTE as I am still runnning SQLIte 3.7.14.1):
CREATE temp TABLE stock(id, cid, sid);
CREATE temp TABLE clients(id,name);
CREATE temp TABLE suppliers(id,name);
insert into stock (id) values (1),(2),(3),(4),(5),(6),(7);
UPD
Since LEFT JOIN and RIGHT JOIN while also swapping the tables are
interchangeable, why should this not work?
SELECT ... FROM clients LEFT JOIN ON ... ( suppliers LEFT JOIN stock ON ...)
WHERE ...;
-Ursprüngliche Nachricht-
Von: sqlite-users [mailto:sqlite-users-boun...@mailinglists.sql
Ad 4) not quite,but close. If the index used for a join also contains all the
other fields of that table that are referenced in the query, SQLite can use
those values to avoid reading in the corresponding table row. This saves memory
(no storage for table row consumed), CPU cycles (no going thro
avcat for SQLite works.
I suspect we need to be more careful about how we use the tool.
We'll now time the results of each query and run them twice to see the affect.
No idea how long this will take but suspect a few hours :) I will post back the
results as other people may (or may not) find
>On 17 Mar 2017, at 10:20am, Rob Willett wrote:
>
>> CREATE INDEX "Disruptions_idx4" ON Disruptions ("status" COLLATE NOCASE ASC);
>>
>> […]
>>
>> As part of the larger more complex query, we are executing the query
>>
>> ```
>> select * from Disruptions where status = 2 OR status = 6;
>
>The sche
>On 17 Mar 2017, at 10:20am, Rob Willett wrote:
>
>> CREATE INDEX "Disruptions_idx4" ON Disruptions ("status" COLLATE NOCASE ASC);
>>
>> […]
>>
>> As part of the larger more complex query, we are executing the query
>>
>> ```
>> select * from Disruptions where status = 2 OR status = 6;
>
>The sche
A parameterized query enables you to run a fixed query with arbitrary data that
is unknown during compile time, multiple times (once for each set of
parameters), without re-preparing the statement (which is costly) in between.
-Ursprüngliche Nachricht-
Von: sqlite-users [mailto:sqlite-us
Perhaps an analogy will help: Imagine you are given a piano. Pressing keys on
the piano will cause the corresponding tones to be played. If you hit the keys
on the piano with a hammer, then this too will cause tones to be played;
however, it will also most likely cause mechanical failure (i.e. n
Alternatively create a "range" table, insert your defined ranges and
join/subquery to the original query.
Create table range (label text, from integer, to integer);
-Ursprüngliche Nachricht-
Von: sqlite-users [mailto:sqlite-users-boun...@mailinglists.sqlite.org] Im
Auftrag von Simon Sla
ekonk, MA 02771
Cell: (508) - 954 - 2536
EMail: jacob.syl...@gmail.com
Web: http://www.jacobsylvia.com
On Mar 6, 2017 7:23 AM, "Hick Gunter" wrote:
> From sql shell (from a file works the same way):
>
> asql> create temp table test (a text); insert into test values(
From sql shell (from a file works the same way):
asql> create temp table test (a text);
asql> insert into test values('a
...> b
...> c
...> d');
rows inserted
-
1
asql> select * from test;
a
--
a
b
c
d
-Ursprüngliche Nachricht-
Von: sqlite-users [mailto:sq
AFAICT It is not the new value of the integer but rather the new contents of
the blob field that causes the record image to grow and exceed the previously
allocated space, which means the row has to move. Rewriting the record and thus
expiring the blob handle is triggered by the update of the ot
YES. AFAIK if SQLite detects that the rows are/can be made to be returned in
GROUP BY order it can use internal variables to accumulate the group results.
This is expected to be significantly faster than locating and updating a
temporary BTree row for each record scanned.
-Ursprüngliche Nac
qlite-users-boun...@mailinglists.sqlite.org] Im
>Auftrag von R Smith
>Gesendet: Donnerstag, 02. März 2017 16:10
>An: sqlite-users@mailinglists.sqlite.org
>Betreff: Re: [sqlite] Non-unique columns in unique index
>
>
>On 2017/03/02 4:44 PM, Keith Medcalf wrote:
>> On Thursday, 2 March, 2017
I tried to create a test table and two indices thus:
>create temp table test (id integer primary key, name text unique, bs integer,
>data text);
>create unique index plain on test(name);
>create unique index cover on test(name,bs);
NB: The field name has a unique constraint
As long as the query
Not directly, but you can query the locks on the file as per documentation:
struct flockv_pending; // = { F_WRLCK, SEEK_SET, PENDING_BYTE ,
1, 0};
struct flockv_reserved; // = { F_WRLCK, SEEK_SET, RESERVED_BYTE ,
1, 0};
struct flockv_shared;//
You are literally mixing apples and oranges without creating a superclass
"fruit" that contains a field to tell them apart and a set of attributes
(=fields) merged from the attributes of the component tables.
-Ursprüngliche Nachricht-
Von: sqlite-users [mailto:sqlite-users-boun...@mailin
sprüngliche Nachricht-
Von: sqlite-users [mailto:sqlite-users-boun...@mailinglists.sqlite.org] Im
Auftrag von James K. Lowden
Gesendet: Dienstag, 28. Februar 2017 22:41
An: sqlite-users@mailinglists.sqlite.org
Betreff: Re: [sqlite] foreign key cardinality
On Tue, 28 Feb 2017 17:13:30 +
Hick
lto:sqlite-users-boun...@mailinglists.sqlite.org] Im
Auftrag von James K. Lowden
Gesendet: Dienstag, 28. Februar 2017 17:42
An: sqlite-users@mailinglists.sqlite.org
Betreff: Re: [sqlite] foreign key cardinality
On Tue, 28 Feb 2017 08:48:02 +
Hick Gunter wrote:
> "If they are not the pri
Looks like attempting to dereference a NULL pointer. Without a backtrace of the
call stack this is not of much use. Most commonly this is caused by an
uninitialized variable on the stack, accessing a structure that has been
freed/garbage collected or memory being clobbered by a rogue write opera
If a is already unique, there is no need for b in the primary key...
-Ursprüngliche Nachricht-
Von: sqlite-users [mailto:sqlite-users-boun...@mailinglists.sqlite.org] Im
Auftrag von Simon Slavin
Gesendet: Dienstag, 28. Februar 2017 01:41
An: SQLite mailing list
Betreff: Re: [sqlite] fore
Your assumption does not correspond with the documentation, see
http://sqlite.org/foreignkeys.html :
"The parent key is the column or set of columns in the parent table that the
foreign key constraint refers to. This is normally, but not always, the primary
key of the parent table. The parent k
A CHECK constraint is just a special trigger that allows you to raise an error
and only runs on INSERT and UPDATE.
It has nothing to do with internal database structure (pragma integrity_check)
or with foreign keys (pragma foreign_key_check; you have to enable foreign key
checking first anyway)
Definitely 'D' as in "Disk I/O", if you type "1" while runing top, the results
for each CPU are displayed separately und you will find at least 1 line (not
necessarily always the same line) with a significant percentage of "wa" (I/O
wait state).
Apparently your transactions involve very much mo
The unix mv command does not affect currently open file handles, only the
directory entry or entries (atomically, unless it is a cross-filesystem mv,
which is accomplished by pretrending you said cp and is in no way atomic).
As long as the first command shell is running, it will continue to see
Maybe the original intent was to count all the rows in all the tables
separately and return a vector of record counts, as a poor man's integrity
check to make sure no rows got lost. Like
Select (select count() from t1) as t1,(select count() from t2) as t2, ...;
-Ursprüngliche Nachricht-
The beauty of SQLite lies in its user extensability. If you want a presentation
layer function in SQLite you can always write your own custom function, without
forcing your specific needs on the community as a whole.
e.g. print_money( [, ])
with a check that is actually an integer (and not a f
sqlite.org] Im
Auftrag von Dominique Devienne
Gesendet: Mittwoch, 08. Februar 2017 16:42
An: SQLite mailing list
Betreff: Re: [sqlite] Virtual table vs real table query performance
On Wed, Feb 8, 2017 at 4:30 PM, Hick Gunter wrote:
> Values are for retrieving 100.000 rows with a whe
Auftrag von Bob Friesenhahn
Gesendet: Mittwoch, 08. Februar 2017 15:39
An: SQLite mailing list
Betreff: Re: [sqlite] Virtual table vs real table query performance
On Wed, 8 Feb 2017, Hick Gunter wrote:
> Having imlemented a memory-based virtual table complete with indices,
> full table
Having imlemented a memory-based virtual table complete with indices, full
table scan and direct access via rowid (which happens to be the memory address
of the row) I can do a batch delete of 100.000 rows (in a table with 1
composite index) in about 2 seconds (3.7 seconds with the condition) wh
Did you look at the syntax diagrams? If you mean giving names to foreign key
clauses, then no.
-Ursprüngliche Nachricht-
Von: sqlite-users [mailto:sqlite-users-boun...@mailinglists.sqlite.org] Im
Auftrag von Igor Korot
Gesendet: Mittwoch, 08. Februar 2017 06:04
An: Discussion of SQLite D
= "Select
@@Identity" ... int iKeyID = (int)oledbCmd.ExecuteScalar()?
On Mon, Feb 6, 2017 at 1:55 AM, Hick Gunter wrote:
> But only if you can guarantee that your statement inserts exactly one record
> and that nothing is executed on your connection between the insert
Yes, putting a large number of inserts that affect the same table(s) into ona
bulk transaction can be a huge speedup, because the operations can take place
in memory without having to reach the disk surface until commit time.
The optimal number of inserts/transaction depends on your hardware set
But only if you can guarantee that your statement inserts exactly one record
and that nothing is executed on your connection between the insert and the call.
-Ursprüngliche Nachricht-
Von: sqlite-users [mailto:sqlite-users-boun...@mailinglists.sqlite.org] Im
Auftrag von Chris Locke
Gesen
9', '00', None) (10, 'Column', 1, 6, 4, '99', '00', None) (11,
'Ge', 4, 20, 3, '(BINARY)', '53', None) (12, 'IdxRowid', 3, 5, 0, '', '00',
None) (13, 'SeekGE', 4, 20, 5, '1'
The supported constraints are:
#define SQLITE_INDEX_CONSTRAINT_EQ 2
#define SQLITE_INDEX_CONSTRAINT_GT 4
#define SQLITE_INDEX_CONSTRAINT_LE 8
#define SQLITE_INDEX_CONSTRAINT_LT 16
#define SQLITE_INDEX_CONSTRAINT_GE 32
#define SQLITE_INDEX_CONSTRAINT_MATCH 64
#define SQLITE_
It will if you add AUTOINCREMENT
-Ursprüngliche Nachricht-
Von: sqlite-users [mailto:sqlite-users-boun...@mailinglists.sqlite.org] Im
Auftrag von Clyde Eisenbeis
Gesendet: Donnerstag, 02. Februar 2017 15:12
An: SQLite mailing list
Betreff: Re: [sqlite] Does SQLite use field definitions?
Sorry misread that you are attempting to write a custom collation.
-Ursprüngliche Nachricht-
Von: sqlite-users [mailto:sqlite-users-boun...@mailinglists.sqlite.org] Im
Auftrag von Hick Gunter
Gesendet: Donnerstag, 02. Februar 2017 09:06
An: 'SQLite mailing list'
Betreff: R
DISTINCT forces the query optimizer to create an intermediate table to hold the
results and compare each row of the non-distinct result set with an
automatically created index. It may also affect the query plan in a way that
chooses inefficient indices, which is more likely if you have not run A
The interface your (simple) function must support is:
void xFunc(sqlite3_context*,int,sqlite3_value**)
with the first parameter being the sqlite3_context,
the second parameter being the number of arguments passed in, and
the third parameter being an array of pointers to unprotected sqlite3_value
Yes. See http://sqlite.org/lang_createtable.html for details. I also suggest
you look at http://sqlite.org/datatype3.html too
-Ursprüngliche Nachricht-
Von: sqlite-users [mailto:sqlite-users-boun...@mailinglists.sqlite.org] Im
Auftrag von Clyde Eisenbeis
Gesendet: Dienstag, 31. Jänner 20
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