diff options
Diffstat (limited to 'src/sqlite.h.in')
| -rw-r--r-- | src/sqlite.h.in | 29 |
1 files changed, 27 insertions, 2 deletions
diff --git a/src/sqlite.h.in b/src/sqlite.h.in index 471b7f526..8934d729e 100644 --- a/src/sqlite.h.in +++ b/src/sqlite.h.in @@ -4360,7 +4360,7 @@ int sqlite3_value_type(sqlite3_value*); int sqlite3_value_numeric_type(sqlite3_value*); /* -** CAPI3REF: Obtaining SQL Values +** CAPI3REF: Finding The Subtype Of SQL Values ** METHOD: sqlite3_value ** ** The sqlite3_value_subtype(V) function returns the subtype for @@ -5634,13 +5634,31 @@ struct sqlite3_module { ** ^The estimatedRows value is an estimate of the number of rows that ** will be returned by the strategy. ** +** The xBestIndex method may optionally populate the idxFlags field with a +** mask of SQLITE_INDEX_SCAN_* flags. Currently there is only one such flag - +** SQLITE_INDEX_SCAN_UNIQUE. If the xBestIndex method sets this flag, SQLite +** assumes that the strategy may visit at most one row. +** +** Additionally, if xBestIndex sets the SQLITE_INDEX_SCAN_UNIQUE flag, then +** SQLite also assumes that if a call to the xUpdate() method is made as +** part of the same statement to delete or update a virtual table row and the +** implementation returns SQLITE_CONSTRAINT, then there is no need to rollback +** any database changes. In other words, if the xUpdate() returns +** SQLITE_CONSTRAINT, the database contents must be exactly as they were +** before xUpdate was called. By contrast, if SQLITE_INDEX_SCAN_UNIQUE is not +** set and xUpdate returns SQLITE_CONSTRAINT, any database changes made by +** the xUpdate method are automatically rolled back by SQLite. +** ** IMPORTANT: The estimatedRows field was added to the sqlite3_index_info ** structure for SQLite version 3.8.2. If a virtual table extension is ** used with an SQLite version earlier than 3.8.2, the results of attempting ** to read or write the estimatedRows field are undefined (but are likely ** to included crashing the application). The estimatedRows field should ** therefore only be used if [sqlite3_libversion_number()] returns a -** value greater than or equal to 3008002. +** value greater than or equal to 3008002. Similarly, the idxFlags field +** was added for version 3.8.12. It may therefore only be used if +** sqlite3_libversion_number() returns a value greater than or equal to +** 3008012. */ struct sqlite3_index_info { /* Inputs */ @@ -5668,9 +5686,16 @@ struct sqlite3_index_info { double estimatedCost; /* Estimated cost of using this index */ /* Fields below are only available in SQLite 3.8.2 and later */ sqlite3_int64 estimatedRows; /* Estimated number of rows returned */ + /* Fields below are only available in SQLite 3.8.12 and later */ + int idxFlags; /* Mask of SQLITE_INDEX_SCAN_* flags */ }; /* +** CAPI3REF: Virtual Table Scan Flags +*/ +#define SQLITE_INDEX_SCAN_UNIQUE 1 /* Scan visits at most 1 row */ + +/* ** CAPI3REF: Virtual Table Constraint Operator Codes ** ** These macros defined the allowed values for the |