... 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 ... 

6. Sorting, Grouping and Compound SELECTs  ... When grouping values with the GROUP BY clause values with different storage classes are considered distinct, except for INTEGER and REAL values which are considered equal if they are numerically equal. No affinities are applied to any values as the ... 

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 ... 

 ... 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 ... 

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 ... 

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 ... 

5. Network Bandwidth The core idea behind the protocol is that the replica sends cryptographic hashes for pages or groups of pages over to the origin side. The origin sends back page content that differs, or requests finer-grain hashes if a multi ... 

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 ... 

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 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 ...