func (p *planner) prepare(stmt parser.Statement) (planNode, *roachpb.Error) {
p.prepareOnly = true
switch n := stmt.(type) {
case *parser.Delete:
return p.Delete(n)
case *parser.Insert:
return p.Insert(n, false)
case *parser.Select:
return p.Select(n)
case *parser.Show:
return p.Show(n)
case *parser.ShowColumns:
return p.ShowColumns(n)
case *parser.ShowDatabases:
return p.ShowDatabases(n)
case *parser.ShowGrants:
return p.ShowGrants(n)
case *parser.ShowIndex:
return p.ShowIndex(n)
case *parser.ShowTables:
return p.ShowTables(n)
case *parser.Update:
return p.Update(n)
default:
return nil, roachpb.NewUErrorf("prepare statement not supported: %s", stmt.StatementTag())
// TODO(mjibson): add support for parser.Values.
// Broken because it conflicts with INSERT's use of VALUES.
}
}
// the current transaction might have been committed/rolled back when this returns.
func (e *Executor) execStmt(
stmt parser.Statement, planMaker *planner, autoCommit bool,
) (Result, error) {
var result Result
plan, err := planMaker.makePlan(stmt, nil, autoCommit)
if err != nil {
return result, err
}
if err := plan.Start(); err != nil {
return result, err
}
result.PGTag = stmt.StatementTag()
result.Type = stmt.StatementType()
switch result.Type {
case parser.RowsAffected:
result.RowsAffected += countRowsAffected(plan)
case parser.Rows:
result.Columns = plan.Columns()
for _, c := range result.Columns {
if err := checkResultDatum(c.Typ); err != nil {
return result, err
}
}
// valuesAlloc is used to allocate the backing storage for the
// ResultRow.Values slices in chunks.
var valuesAlloc []parser.Datum
const maxChunkSize = 64 // Arbitrary, could use tuning.
chunkSize := 4 // Arbitrary as well.
for plan.Next() {
// The plan.Values DTuple needs to be copied on each iteration.
values := plan.Values()
n := len(values)
if len(valuesAlloc) < n {
valuesAlloc = make([]parser.Datum, len(result.Columns)*chunkSize)
if chunkSize < maxChunkSize {
chunkSize *= 2
}
}
row := ResultRow{Values: valuesAlloc[:0:n]}
valuesAlloc = valuesAlloc[n:]
for _, val := range values {
if err := checkResultDatum(val); err != nil {
return result, err
}
row.Values = append(row.Values, val)
}
result.Rows = append(result.Rows, row)
}
}
return result, plan.Err()
}
// the current transaction might have been committed/rolled back when this returns.
func (e *Executor) execStmt(
stmt parser.Statement, planMaker *planner,
timestamp time.Time, autoCommit bool) (Result, *roachpb.Error) {
var result Result
plan, pErr := planMaker.makePlan(stmt, autoCommit)
if pErr != nil {
return result, pErr
}
result.PGTag = stmt.StatementTag()
result.Type = stmt.StatementType()
switch result.Type {
case parser.RowsAffected:
result.RowsAffected += countRowsAffected(plan)
case parser.Rows:
result.Columns = plan.Columns()
for _, c := range result.Columns {
if err := checkResultDatum(c.Typ); err != nil {
return result, roachpb.NewError(err)
}
}
for plan.Next() {
// The plan.Values DTuple needs to be copied on each iteration.
values := plan.Values()
row := ResultRow{Values: make([]parser.Datum, 0, len(values))}
for _, val := range values {
if err := checkResultDatum(val); err != nil {
return result, roachpb.NewError(err)
}
row.Values = append(row.Values, val)
}
result.Rows = append(result.Rows, row)
}
}
return result, plan.PErr()
}
func (e *Executor) execStmt(stmt parser.Statement, planMaker *planner) (Result, *roachpb.Error) {
var result Result
switch stmt.(type) {
case *parser.BeginTransaction:
if planMaker.txn != nil {
return result, roachpb.NewError(errTransactionInProgress)
}
// Start a transaction here and not in planMaker to prevent begin
// transaction from being called within an auto-transaction below.
planMaker.setTxn(client.NewTxn(e.db), time.Now())
planMaker.txn.SetDebugName("sql", 0)
case *parser.CommitTransaction, *parser.RollbackTransaction:
if planMaker.txn == nil {
return result, roachpb.NewError(errNoTransactionInProgress)
} else if planMaker.txn.Proto.Status == roachpb.ABORTED {
// Reset to allow starting a new transaction.
planMaker.resetTxn()
return result, nil
}
case *parser.SetTransaction:
if planMaker.txn == nil {
return result, roachpb.NewError(errNoTransactionInProgress)
}
default:
if planMaker.txn != nil && planMaker.txn.Proto.Status == roachpb.ABORTED {
return result, roachpb.NewError(&roachpb.SqlTransactionAbortedError{})
}
}
// Bind all the placeholder variables in the stmt to actual values.
if err := parser.FillArgs(stmt, &planMaker.params); err != nil {
return result, roachpb.NewError(err)
}
// Create a function which both makes and executes the plan, populating
// result.
//
// TODO(pmattis): Should this be a separate function? Perhaps we should move
// some of the common code back out into execStmts and have execStmt contain
// only the body of this closure.
f := func(timestamp time.Time, autoCommit bool) *roachpb.Error {
planMaker.evalCtx.StmtTimestamp = parser.DTimestamp{Time: timestamp}
plan, pErr := planMaker.makePlan(stmt, autoCommit)
if pErr != nil {
return pErr
}
result.PGTag = stmt.StatementTag()
result.Type = stmt.StatementType()
switch result.Type {
case parser.RowsAffected:
for plan.Next() {
result.RowsAffected++
}
case parser.Rows:
result.Columns = plan.Columns()
for _, c := range result.Columns {
if err := checkResultDatum(c.Typ); err != nil {
return err
}
}
for plan.Next() {
// The plan.Values DTuple needs to be copied on each iteration.
values := plan.Values()
row := ResultRow{Values: make([]parser.Datum, 0, len(values))}
for _, val := range values {
if err := checkResultDatum(val); err != nil {
return err
}
row.Values = append(row.Values, val)
}
result.Rows = append(result.Rows, row)
}
}
return plan.PErr()
}
// If there is a pending transaction.
if planMaker.txn != nil {
pErr := f(time.Now(), false)
return result, pErr
}
if testingWaitForMetadata {
// We might need to verify metadata. Lock the system config so that
// no gossip updates sneak in under us.
// This lock does not change semantics. Even outside of tests, the
// planner is initialized with a static systemConfig, so locking
// the Executor's systemConfig cannot change the semantics of the
// SQL operation being performed under lock.
//
// The case of a multi-request transaction is not handled here,
// because those transactions outlive the verification callback.
// This can be addressed when we move to a connection-oriented
// protocol and server-side transactions.
e.systemConfigCond.L.Lock()
defer e.systemConfigCond.L.Unlock()
}
// No transaction. Run the command as a retryable block in an
// auto-transaction.
if pErr := e.db.Txn(func(txn *client.Txn) *roachpb.Error {
timestamp := time.Now()
planMaker.setTxn(txn, timestamp)
pErr := f(timestamp, true)
planMaker.resetTxn()
return pErr
}); pErr != nil {
return result, pErr
}
if testingWaitForMetadata {
if verify := planMaker.testingVerifyMetadata; verify != nil {
// In the case of a multi-statement request, avoid reusing this
// callback.
planMaker.testingVerifyMetadata = nil
for i := 0; ; i++ {
if verify(e.systemConfig) != nil {
e.systemConfigCond.Wait()
} else {
if i == 0 {
return result, roachpb.NewErrorf("expected %q to require a gossip update, but it did not", stmt)
} else if i > 1 {
log.Infof("%q unexpectedly required %d gossip updates", stmt, i)
}
break
}
}
}
}
return result, nil
}