Small. Fast. Reliable.
Choose any three.
Choose any three.
|
UPDATE
(lang_update.html)
... UPDATE inventory
SET quantity = quantity - daily.amt
FROM (SELECT sum(quantity) AS amt, itemId FROM sales GROUP BY 2) AS daily
WHERE inventory.itemId = daily.itemId;
The subquery in the FROM clause computes the amount by which the
inventory should ...
|
|
The SQLite OS Interface or "VFS"
(vfs.html)
3.5. Other Example VFSes
... An auxiliary
interface is used to define "quota groups". A quota group is a
set of files (database files, journals, and temporary files) whose
names all match a GLOB pattern. The sum of the sizes of all files
in each ...
|
|
Most Widely Deployed SQL Database Engine
(mostdeployed.html)
... The original reference implementation for
libpng
Libjpeg from the Independent JPEG Group
Libc is omitted from the above list even though
it is more common than SQLite because
libc is not a single software component but rather several
competing implementations ...
|
|
Profiling SQL Queries
(profile.html)
3. Complex Cases - Rows, Loops and Cycles
... sqlite3> WITH cnt(i) AS (
SELECT 1 UNION SELECT i+1 FROM cnt WHERE i<100
)
SELECT
*, (SELECT d FROM t2 WHERE c=ft.rowid)
FROM
(SELECT count(*), a FROM t1 GROUP BY a) AS v1 CROSS JOIN ...
|
|
Temporary Files Used By SQLite
(tempfiles.html)
2.8. Transient Indices
... SQLite implements GROUP BY by ordering the output rows in the
order suggested by the GROUP BY terms. Each output row is
compared to the previous to see if it starts a new "group".
The ordering by GROUP BY terms ...
|
|
C API: Determine if a virtual table query is DISTINCT
(c3ref/vtab_distinct.html)
sqlite3_vtab_distinct()
... This mode is used when the query planner
is doing a GROUP BY.
If the sqlite3_vtab_distinct() interface returns 2, that means
that the query planner does not need the rows returned in any particular
order, as long as rows with ...
|
|
The CSV Virtual Table
(csv.html)
1. Overview
... One can use the CSV virtual table inside subqueries,
or common table expressions or add WHERE, GROUP BY, HAVING, ORDER BY,
and LIMIT clauses as required.
|
|
SQLite Database Speed Comparison
(speed.html)
... SQLite works best if you group multiple operations together into
a single transaction.
The results presented here come with the following caveats:
These tests did not attempt to measure multi-user performance or
optimization of complex queries involving multiple joins ...
|
|
The Checksum VFS Shim
(cksumvfs.html)
5. Verification Of Checksums
... SELECT count(*), verify_checksum(data)
FROM sqlite_dbpage
GROUP BY 2;
There are three possible outputs from the verify_checksum()
function: 1, 0, and NULL. 1 is returned if the checksum is
correct. 0 is returned if the checksum is incorrect. NULL
is ...
|
|
STRICT Tables
(stricttables.html)
1. Introduction
... For this latter group, SQLite supports a strict typing
mode, as of version 3.37.0 (2021-11-27), that is enabled
separately for each table.
|
Page generated by FTS5 in about 40.08 ms.