Clarifications to the documentation for the sqlite3_aggregate_context() API.

Also, shorten an over-length source line in sqlite.h.in.

FossilOrigin-Name: 4fe2db1d866c80fe51f7fddbf9ce6753fb55b5f6

1 files changed, 8 insertions, 4 deletions

diff --git a/src/sqlite.h.in b/src/sqlite.h.in
index 0373353d7..a6f9b0b37 100644
--- a/src/sqlite.h.in
+++ b/src/sqlite.h.in
@@ -3993,7 +3993,8 @@ SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*);
 SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
 SQLITE_DEPRECATED int sqlite3_global_recover(void);
 SQLITE_DEPRECATED void sqlite3_thread_cleanup(void);
-SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),void*,sqlite3_int64);
+SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),
+                      void*,sqlite3_int64);
 #endif
 
 /*
@@ -4073,14 +4074,17 @@ int sqlite3_value_numeric_type(sqlite3_value*);
 ** In those cases, sqlite3_aggregate_context() might be called for the
 ** first time from within xFinal().)^
 **
-** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer if N is
-** less than or equal to zero or if a memory allocate error occurs.
+** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer 
+** when first called if N is less than or equal to zero or if a memory
+** allocate error occurs.
 **
 ** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is
 ** determined by the N parameter on first successful call.  Changing the
 ** value of N in subsequent call to sqlite3_aggregate_context() within
 ** the same aggregate function instance will not resize the memory
-** allocation.)^
+** allocation.)^  Within the xFinal callback, it is customary to set
+** N=0 in calls to sqlite3_aggregate_context(C,N) so that no 
+** pointless memory allocations occur.
 **
 ** ^SQLite automatically frees the memory allocated by 
 ** sqlite3_aggregate_context() when the aggregate query concludes.