Declared type.

README.md

@@ -47,7 +47,7 @@ and uses [wazero](https://wazero.io/) to provide `cgo`-free SQLite bindings.
 - [x] [virtual tables](https://sqlite.org/vtab.html)
 - [x] [custom VFSes](https://sqlite.org/vfs.html)
 - [x] [online backup](https://sqlite.org/backup.html)
-- [x] [JSON support](https://www.sqlite.org/json1.html)
+- [x] [JSON support](https://sqlite.org/json1.html)
 - [x] [Unicode support](https://sqlite.org/src/dir/ext/icu)
 
 ### Caveats

driver/driver.go

@@ -458,6 +458,16 @@ func (r *rows) Columns() []string {
 	return columns
 }
 
+func (r *rows) ColumnTypeDatabaseTypeName(index int) string {
+	decltype := r.Stmt.ColumnDeclType(index)
+	if len := len(decltype); len > 0 && decltype[len-1] == ')' {
+		if i := strings.LastIndexByte(decltype, '('); i >= 0 {
+			decltype = decltype[:i]
+		}
+	}
+	return strings.ToUpper(strings.TrimSpace(decltype))
+}
+
 func (r *rows) Next(dest []driver.Value) error {
 	old := r.Conn.SetInterrupt(r.ctx)
 	defer r.Conn.SetInterrupt(old)

embed/exports.txt

@@ -1,95 +1,97 @@
 free
 malloc
 malloc_destructor
-sqlite3_errcode
-sqlite3_errstr
-sqlite3_errmsg
-sqlite3_error_offset
-sqlite3_open_v2
-sqlite3_close
-sqlite3_close_v2
-sqlite3_prepare_v3
-sqlite3_finalize
-sqlite3_reset
-sqlite3_step
-sqlite3_exec
-sqlite3_interrupt
-sqlite3_progress_handler_go
-sqlite3_clear_bindings
+sqlite3_aggregate_context
+sqlite3_anycollseq_init
+sqlite3_backup_finish
+sqlite3_backup_init
+sqlite3_backup_pagecount
+sqlite3_backup_remaining
+sqlite3_backup_step
+sqlite3_bind_blob64
+sqlite3_bind_double
+sqlite3_bind_int64
+sqlite3_bind_null
 sqlite3_bind_parameter_count
 sqlite3_bind_parameter_index
 sqlite3_bind_parameter_name
-sqlite3_bind_null
-sqlite3_bind_int64
-sqlite3_bind_double
-sqlite3_bind_text64
-sqlite3_bind_blob64
-sqlite3_bind_zeroblob64
 sqlite3_bind_pointer_go
+sqlite3_bind_text64
 sqlite3_bind_value
-sqlite3_column_count
-sqlite3_column_name
-sqlite3_column_type
-sqlite3_column_int64
-sqlite3_column_double
-sqlite3_column_text
+sqlite3_bind_zeroblob64
+sqlite3_blob_bytes
+sqlite3_blob_close
+sqlite3_blob_open
+sqlite3_blob_read
+sqlite3_blob_reopen
+sqlite3_blob_write
+sqlite3_changes64
+sqlite3_clear_bindings
+sqlite3_close
+sqlite3_close_v2
 sqlite3_column_blob
 sqlite3_column_bytes
+sqlite3_column_count
+sqlite3_column_decltype
+sqlite3_column_double
+sqlite3_column_int64
+sqlite3_column_name
+sqlite3_column_text
+sqlite3_column_type
 sqlite3_column_value
-sqlite3_blob_open
-sqlite3_blob_close
-sqlite3_blob_reopen
-sqlite3_blob_bytes
-sqlite3_blob_read
-sqlite3_blob_write
-sqlite3_backup_init
-sqlite3_backup_step
-sqlite3_backup_finish
-sqlite3_backup_remaining
-sqlite3_backup_pagecount
-sqlite3_uri_parameter
-sqlite3_uri_key
-sqlite3_changes64
-sqlite3_last_insert_rowid
-sqlite3_get_autocommit
+sqlite3_create_aggregate_function_go
 sqlite3_create_collation_go
 sqlite3_create_function_go
-sqlite3_create_aggregate_function_go
-sqlite3_create_window_function_go
 sqlite3_create_module_go
-sqlite3_overload_function
-sqlite3_anycollseq_init
-sqlite3_aggregate_context
-sqlite3_user_data
-sqlite3_set_auxdata_go
+sqlite3_create_window_function_go
+sqlite3_declare_vtab
+sqlite3_errcode
+sqlite3_errmsg
+sqlite3_error_offset
+sqlite3_errstr
+sqlite3_exec
+sqlite3_finalize
+sqlite3_get_autocommit
 sqlite3_get_auxdata
-sqlite3_value_type
-sqlite3_value_int64
-sqlite3_value_double
-sqlite3_value_text
-sqlite3_value_blob
-sqlite3_value_bytes
-sqlite3_value_pointer_go
-sqlite3_value_nochange
-sqlite3_result_null
-sqlite3_result_int64
-sqlite3_result_double
-sqlite3_result_text64
+sqlite3_interrupt
+sqlite3_last_insert_rowid
+sqlite3_open_v2
+sqlite3_overload_function
+sqlite3_prepare_v3
+sqlite3_progress_handler_go
+sqlite3_reset
 sqlite3_result_blob64
-sqlite3_result_zeroblob64
-sqlite3_result_pointer_go
-sqlite3_result_value
+sqlite3_result_double
 sqlite3_result_error
 sqlite3_result_error_code
 sqlite3_result_error_nomem
 sqlite3_result_error_toobig
-sqlite3_declare_vtab
-sqlite3_vtab_config_go
+sqlite3_result_int64
+sqlite3_result_null
+sqlite3_result_pointer_go
+sqlite3_result_text64
+sqlite3_result_value
+sqlite3_result_zeroblob64
+sqlite3_set_auxdata_go
+sqlite3_step
+sqlite3_stmt_readonly
+sqlite3_uri_key
+sqlite3_uri_parameter
+sqlite3_user_data
+sqlite3_value_blob
+sqlite3_value_bytes
+sqlite3_value_double
+sqlite3_value_int64
+sqlite3_value_nochange
+sqlite3_value_pointer_go
+sqlite3_value_text
+sqlite3_value_type
 sqlite3_vtab_collation
+sqlite3_vtab_config_go
 sqlite3_vtab_distinct
 sqlite3_vtab_in
 sqlite3_vtab_in_first
 sqlite3_vtab_in_next
-sqlite3_vtab_rhs_value
 sqlite3_vtab_nochange
-sqlite3_vtab_on_conflict
+sqlite3_vtab_on_conflict
+sqlite3_vtab_rhs_value

ext/statement/stmt.go

@@ -56,7 +56,9 @@ func (t *table) declare() error {
 	if tail != "" {
 		return fmt.Errorf("statement: multiple statements")
 	}
-	// TODO: sqlite3_stmt_readonly
+	if !stmt.ReadOnly() {
+		return fmt.Errorf("statement: statement must be read only")
+	}
 
 	t.inputs = stmt.BindCount()
 	t.outputs = stmt.ColumnCount()
@@ -68,14 +70,17 @@ func (t *table) declare() error {
 		str.WriteString(sep)
 		name := stmt.ColumnName(i)
 		str.WriteString(sqlite3.QuoteIdentifier(name))
-		// TODO: sqlite3_column_decltype
+		if typ := stmt.ColumnDeclType(i); typ != "" {
+			str.WriteByte(' ')
+			str.WriteString(typ)
+		}
 		sep = ","
 	}
 	for i := 1; i <= t.inputs; i++ {
 		str.WriteString(sep)
 		name := stmt.BindName(i)
 		if name == "" {
-			str.WriteByte('\'')
+			str.WriteString("'")
 			str.WriteString(strconv.Itoa(i))
 			str.WriteString("' HIDDEN")
 		} else {

sqlite3/sqlite_cfg.h

@@ -37,11 +37,12 @@
 #define SQLITE_DEFAULT_WAL_SYNCHRONOUS 1
 #define SQLITE_LIKE_DOESNT_MATCH_BLOBS
 #define SQLITE_MAX_EXPR_DEPTH 0
-#define SQLITE_OMIT_DECLTYPE
+#define SQLITE_USE_ALLOCA
 #define SQLITE_OMIT_DEPRECATED
 #define SQLITE_OMIT_SHARED_CACHE
 #define SQLITE_OMIT_AUTOINIT
-#define SQLITE_USE_ALLOCA
+// #define SQLITE_OMIT_DECLTYPE
+// #define SQLITE_OMIT_PROGRESS_CALLBACK
 
 // Other Options
 

stmt.go

@@ -90,6 +90,15 @@ func (s *Stmt) Exec() error {
 	return s.Reset()
 }
 
+// ReadOnly returns true if and only if the statement
+// makes no direct changes to the content of the database file.
+//
+// https://sqlite.org/c3ref/stmt_readonly.html
+func (s *Stmt) ReadOnly() bool {
+	r := s.c.call("sqlite3_stmt_readonly", uint64(s.handle))
+	return r != 0
+}
+
 // BindCount returns the number of SQL parameters in the prepared statement.
 //
 // https://sqlite.org/c3ref/bind_parameter_count.html
@@ -344,6 +353,19 @@ func (s *Stmt) ColumnType(col int) Datatype {
 	return Datatype(r)
 }
 
+// ColumnDeclType returns the declared datatype of the result column.
+// The leftmost column of the result set has the index 0.
+//
+// https://sqlite.org/c3ref/column_decltype.html
+func (s *Stmt) ColumnDeclType(col int) string {
+	r := s.c.call("sqlite3_column_decltype",
+		uint64(s.handle), uint64(col))
+	if r == 0 {
+		return ""
+	}
+	return util.ReadString(s.c.mod, uint32(r), _MAX_NAME)
+}
+
 // ColumnBool returns the value of the result column as a bool.
 // The leftmost column of the result set has the index 0.
 // SQLite does not have a separate boolean storage class.

tests/driver_test.go

@@ -72,6 +72,17 @@ func TestDriver(t *testing.T) {
 	}
 	defer rows.Close()
 
+	typs, err := rows.ColumnTypes()
+	if err != nil {
+		t.Fatal(err)
+	}
+	if got := typs[0].DatabaseTypeName(); got != "INT" {
+		t.Errorf("got %s, want INT", got)
+	}
+	if got := typs[1].DatabaseTypeName(); got != "VARCHAR" {
+		t.Errorf("got %s, want INT", got)
+	}
+
 	row := 0
 	ids := []int{0, 1, 2}
 	names := []string{"go", "zig", "whatever"}