diff options
Diffstat (limited to '')
| -rw-r--r-- | src/sqlite.h.in | 63 |
1 files changed, 45 insertions, 18 deletions
diff --git a/src/sqlite.h.in b/src/sqlite.h.in index 7acdde8..549b52a 100644 --- a/src/sqlite.h.in +++ b/src/sqlite.h.in @@ -764,11 +764,11 @@ struct sqlite3_file { ** </ul> ** xLock() upgrades the database file lock. In other words, xLock() moves the ** database file lock in the direction NONE toward EXCLUSIVE. The argument to -** xLock() is always on of SHARED, RESERVED, PENDING, or EXCLUSIVE, never +** xLock() is always one of SHARED, RESERVED, PENDING, or EXCLUSIVE, never ** SQLITE_LOCK_NONE. If the database file lock is already at or above the ** requested lock, then the call to xLock() is a no-op. ** xUnlock() downgrades the database file lock to either SHARED or NONE. -* If the lock is already at or below the requested lock state, then the call +** If the lock is already at or below the requested lock state, then the call ** to xUnlock() is a no-op. ** The xCheckReservedLock() method checks whether any database connection, ** either in this process or in some other process, is holding a RESERVED, @@ -3305,8 +3305,8 @@ int sqlite3_set_authorizer( #define SQLITE_RECURSIVE 33 /* NULL NULL */ /* -** CAPI3REF: Tracing And Profiling Functions -** METHOD: sqlite3 +** CAPI3REF: Deprecated Tracing And Profiling Functions +** DEPRECATED ** ** These routines are deprecated. Use the [sqlite3_trace_v2()] interface ** instead of the routines described here. @@ -6887,6 +6887,12 @@ int sqlite3_autovacuum_pages( ** The exceptions defined in this paragraph might change in a future ** release of SQLite. ** +** Whether the update hook is invoked before or after the +** corresponding change is currently unspecified and may differ +** depending on the type of change. Do not rely on the order of the +** hook call with regards to the final result of the operation which +** triggers the hook. +** ** The update hook implementation must not do anything that will modify ** the database connection that invoked the update hook. Any actions ** to modify the database connection must be deferred until after the @@ -8357,7 +8363,7 @@ int sqlite3_test_control(int op, ...); ** The sqlite3_keyword_count() interface returns the number of distinct ** keywords understood by SQLite. ** -** The sqlite3_keyword_name(N,Z,L) interface finds the N-th keyword and +** The sqlite3_keyword_name(N,Z,L) interface finds the 0-based N-th keyword and ** makes *Z point to that keyword expressed as UTF8 and writes the number ** of bytes in the keyword into *L. The string that *Z points to is not ** zero-terminated. The sqlite3_keyword_name(N,Z,L) routine returns @@ -9936,24 +9942,45 @@ const char *sqlite3_vtab_collation(sqlite3_index_info*,int); ** <li value="2"><p> ** ^(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 same values in all "aOrderBy" columns -** are adjacent.)^ ^(Furthermore, only a single row for each particular -** combination of values in the columns identified by the "aOrderBy" field -** needs to be returned.)^ ^It is always ok for two or more rows with the same -** values in all "aOrderBy" columns to be returned, as long as all such rows -** are adjacent. ^The virtual table may, if it chooses, omit extra rows -** that have the same value for all columns identified by "aOrderBy". -** ^However omitting the extra rows is optional. +** order, as long as rows with the same values in all columns identified +** by "aOrderBy" are adjacent.)^ ^(Furthermore, when two or more rows +** contain the same values for all columns identified by "colUsed", all but +** one such row may optionally be omitted from the result.)^ +** The virtual table is not required to omit rows that are duplicates +** over the "colUsed" columns, but if the virtual table can do that without +** too much extra effort, it could potentially help the query to run faster. ** This mode is used for a DISTINCT query. ** <li value="3"><p> -** ^(If the sqlite3_vtab_distinct() interface returns 3, that means -** that the query planner needs only distinct rows but it does need the -** rows to be sorted.)^ ^The virtual table implementation is free to omit -** rows that are identical in all aOrderBy columns, if it wants to, but -** it is not required to omit any rows. This mode is used for queries +** ^(If the sqlite3_vtab_distinct() interface returns 3, that means the +** virtual table must return rows in the order defined by "aOrderBy" as +** if the sqlite3_vtab_distinct() interface had returned 0. However if +** two or more rows in the result have the same values for all columns +** identified by "colUsed", then all but one such row may optionally be +** omitted.)^ Like when the return value is 2, the virtual table +** is not required to omit rows that are duplicates over the "colUsed" +** columns, but if the virtual table can do that without +** too much extra effort, it could potentially help the query to run faster. +** This mode is used for queries ** that have both DISTINCT and ORDER BY clauses. ** </ol> ** +** <p>The following table summarizes the conditions under which the +** virtual table is allowed to set the "orderByConsumed" flag based on +** the value returned by sqlite3_vtab_distinct(). This table is a +** restatement of the previous four paragraphs: +** +** <table border=1 cellspacing=0 cellpadding=10 width="90%"> +** <tr> +** <td valign="top">sqlite3_vtab_distinct() return value +** <td valign="top">Rows are returned in aOrderBy order +** <td valign="top">Rows with the same value in all aOrderBy columns are adjacent +** <td valign="top">Duplicates over all colUsed columns may be omitted +** <tr><td>0<td>yes<td>yes<td>no +** <tr><td>1<td>no<td>yes<td>no +** <tr><td>2<td>no<td>yes<td>yes +** <tr><td>3<td>yes<td>yes<td>yes +** </table> +** ** ^For the purposes of comparing virtual table output values to see if the ** values are same value for sorting purposes, two NULL values are considered ** to be the same. In other words, the comparison operator is "IS" |