... If the query optimizer is unable to use the index specified by the INDEXED BY clause, then the query will fail with an error. The INDEXED BY clause is not intended for use in tuning the performance of a query ... 

sqlite3_uri_parameter(), sqlite3_uri_boolean(), sqlite3_uri_int64(), sqlite3_uri_key()

These are utility routines, useful to custom VFS implementations, that check if a database file was a URI that contained a specific query parameter, and if so obtains the value of that query parameter. The first parameter to these interfaces ... 

 ... The query in the CREATE VIRTUAL TABLE statement for a union-vtab must be a well-formed SQL query that returns four columns and an arbitrary number of rows. Each row in the result of the query represents a single ... 

3.2. Set Operations Using The Standard Query Syntax FTS query set operations using the standard query syntax are similar, but not identical, to set operations with the enhanced query syntax. There are four differences, as follows: Only the implicit version of the AND operator is supported. Specifying the ... 

6.3. Additional Considerations for Custom Queries The MATCH operator of a custom R*Tree query function must be a top-level AND-connected term of the WHERE clause, or else it will not be usable by the R*Tree query optimizer and the query will not ... 

1. How To Use Indexes On Expressions  ... The two expressions might be mathematically equivalent, but the SQLite query planner insists that they be the same, not merely equivalent. Consider rewriting the query thusly: SELECT * FROM t2 WHERE x+y=22; This second query will likely use the ... 

3. Queries Using Partial Indexes Let X be the expression in the WHERE clause of a partial index, and let W be the WHERE clause of a query that uses the table that is indexed. Then, the query is permitted to use the partial index ... 

 ... However, if an application makes complex queries that have many possible query plans, the query planner will be better able to pick the best plan if ANALYZE has been run. This can result it significant performance improvements for some queries ... 

3. Full-text Query Syntax The following block contains a summary of the FTS query syntax in BNF form. A detailed explanation follows. <phrase> := string [*] <phrase> := <phrase> + <phrase> <neargroup> := NEAR ( <phrase> < ... 

sqlite3_stmt_explain()

 ... Hence, if the SQL text originally began with EXPLAIN or EXPLAIN QUERY PLAN, but sqlite3_stmt_explain(S,0) is called to convert the statement into an ordinary statement, the EXPLAIN or EXPLAIN QUERY PLAN keywords will still appear in the sqlite3_sql ...