// Exec inserts values into the COPY stream. The insert is asynchronous
// and Exec can return errors from previous Exec calls to the same
// COPY stmt.
//
// You need to call Exec(nil) to sync the COPY stream and to get any
// errors from pending data, since Stmt.Close() doesn't return errors
// to the user.
func (ci *copyin) Exec(v []driver.Value) (r driver.Result, err error) {
defer errRecover(&err)
if ci.closed {
return nil, errCopyInClosed
}
if ci.isErrorSet() {
return nil, ci.err
}
if len(v) == 0 {
err = ci.Close()
ci.closed = true
return nil, err
}
numValues := len(v)
for i, value := range v {
ci.buffer = appendEncodedText(&ci.cn.parameterStatus, ci.buffer, value)
if i < numValues-1 {
ci.buffer = append(ci.buffer, '\t')
}
}
ci.buffer = append(ci.buffer, '\n')
if len(ci.buffer) > ciBufferFlushSize {
ci.flush(ci.buffer)
// reset buffer, keep bytes for message identifier and length
ci.buffer = ci.buffer[:5]
}
return driver.RowsAffected(0), nil
}
// parseComplete parses the "command tag" from a CommandComplete message, and
// returns the number of rows affected (if applicable) and a string
// identifying only the command that was executed, e.g. "ALTER TABLE". If the
// command tag could not be parsed, parseComplete panics.
func parseComplete(commandTag string) (driver.Result, string) {
commandsWithAffectedRows := []string{
"SELECT ",
// INSERT is handled below
"UPDATE ",
"DELETE ",
"FETCH ",
"MOVE ",
"COPY ",
}
var affectedRows *string
for _, tag := range commandsWithAffectedRows {
if strings.HasPrefix(commandTag, tag) {
t := commandTag[len(tag):]
affectedRows = &t
commandTag = tag[:len(tag)-1]
break
}
}
// INSERT also includes the oid of the inserted row in its command tag.
// Oids in user tables are deprecated, and the oid is only returned when
// exactly one row is inserted, so it's unlikely to be of value to any
// real-world application and we can ignore it.
if affectedRows == nil && strings.HasPrefix(commandTag, "INSERT ") {
parts := strings.Split(commandTag, " ")
if len(parts) != 3 {
errorf("unexpected INSERT command tag %s", commandTag)
}
affectedRows = &parts[len(parts)-1]
commandTag = "INSERT"
}
// There should be no affected rows attached to the tag, just return it
if affectedRows == nil {
return driver.RowsAffected(0), commandTag
}
n, err := strconv.ParseInt(*affectedRows, 10, 64)
if err != nil {
errorf("could not parse commandTag: %s", err)
}
return driver.RowsAffected(n), commandTag
}
// When doInsert is true, add the row to the table.
// When doInsert is false do prep-work and error checking, but don't
// actually add the row to the table.
func (s *fakeStmt) execInsert(args []driver.Value, doInsert bool) (driver.Result, error) {
db := s.c.db
if len(args) != s.placeholders {
panic("error in pkg db; should only get here if size is correct")
}
db.mu.Lock()
t, ok := db.table(s.table)
db.mu.Unlock()
if !ok {
return nil, fmt.Errorf("fakedb: table %q doesn't exist", s.table)
}
t.mu.Lock()
defer t.mu.Unlock()
var cols []interface{}
if doInsert {
cols = make([]interface{}, len(t.colname))
}
argPos := 0
for n, colname := range s.colName {
colidx := t.columnIndex(colname)
if colidx == -1 {
return nil, fmt.Errorf("fakedb: column %q doesn't exist or dropped since prepared statement was created", colname)
}
var val interface{}
if strvalue, ok := s.colValue[n].(string); ok && strvalue == "?" {
val = args[argPos]
argPos++
} else {
val = s.colValue[n]
}
if doInsert {
cols[colidx] = val
}
}
if doInsert {
t.rows = append(t.rows, &row{cols: cols})
}
return driver.RowsAffected(1), nil
}