Golang parser.Statement類代碼示例

// updateStmtCounts updates metrics for the number of times the different types of SQL
// statements have been received by this node.
func (e *Executor) updateStmtCounts(stmt parser.Statement) {
	e.QueryCount.Inc(1)
	switch stmt.(type) {
	case *parser.BeginTransaction:
		e.TxnBeginCount.Inc(1)
	case *parser.Select:
		e.SelectCount.Inc(1)
	case *parser.Update:
		e.UpdateCount.Inc(1)
	case *parser.Insert:
		e.InsertCount.Inc(1)
	case *parser.Delete:
		e.DeleteCount.Inc(1)
	case *parser.CommitTransaction:
		e.TxnCommitCount.Inc(1)
	case *parser.RollbackTransaction:
		e.TxnRollbackCount.Inc(1)
	default:
		if stmt.StatementType() == parser.DDL {
			e.DdlCount.Inc(1)
		} else {
			e.MiscCount.Inc(1)
		}
	}
}

// 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, autoCommit)
	if err != nil {
		return result, err
	}

	defer plan.Close()

	distSQLMode := testDistSQL
	if planMaker.session.DistSQLMode != distSQLDisabled {
		distSQLMode = planMaker.session.DistSQLMode
	}
	if distSQLMode != distSQLDisabled {
		if err := hackPlanToUseDistSQL(plan, distSQLMode); 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:
		count, err := countRowsAffected(plan)
		if err != nil {
			return result, err
		}
		result.RowsAffected += count

	case parser.Rows:
		result.Columns = plan.Columns()
		for _, c := range result.Columns {
			if err := checkResultType(c.Typ); err != nil {
				return result, err
			}
		}
		result.Rows = NewRowContainer(planMaker.session.makeBoundAccount(), result.Columns, 0)

		next, err := plan.Next()
		for ; next; next, err = plan.Next() {
			// The plan.Values DTuple needs to be copied on each iteration.
			values := plan.Values()

			for _, val := range values {
				if err := checkResultType(val.ResolvedType()); err != nil {
					return result, err
				}
			}
			if _, err := result.Rows.AddRow(values); err != nil {
				return result, err
			}
		}
		if err != nil {
			return result, err
		}
	}
	return result, nil
}

// 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, autoCommit)
	if err != nil {
		return result, err
	}

	defer plan.Close()

	distSQLMode := testDistSQL
	if planMaker.session.DistSQLMode != distSQLDisabled {
		distSQLMode = planMaker.session.DistSQLMode
	}
	if distSQLMode != distSQLDisabled {
		if err := hackPlanToUseDistSQL(plan, distSQLMode); 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:
		count, err := countRowsAffected(plan)
		if err != nil {
			return result, err
		}
		result.RowsAffected += count

	case parser.Rows:
		result.Columns = plan.Columns()
		for _, c := range result.Columns {
			if err := checkResultType(c.Typ); err != nil {
				return result, err
			}
		}
		result.Rows = planMaker.NewRowContainer(
			planMaker.session.makeBoundAccount(),
			result.Columns, 0)

		// valuesAlloc is used to allocate the backing storage for the
		// result row slices in chunks.
		var valuesAlloc []parser.Datum
		const maxChunkSize = 64 // Arbitrary, could use tuning.
		chunkSize := 4          // Arbitrary as well.

		next, err := plan.Next()
		for ; next; next, err = 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.DTuple, len(result.Columns)*chunkSize)
				if chunkSize < maxChunkSize {
					chunkSize *= 2
				}
			}
			row := valuesAlloc[:0:n]
			valuesAlloc = valuesAlloc[n:]

			for _, val := range values {
				if err := checkResultType(val.ResolvedType()); err != nil {
					return result, err
				}
				row = append(row, val)
			}
			if err := result.Rows.AddRow(row); err != nil {
				return result, err
			}
		}
		if err != nil {
			return result, err
		}
	}
	return result, nil
}

// newPlan constructs a planNode from a statement. This is used
// recursively by the various node constructors.
func (p *planner) newPlan(
	stmt parser.Statement, desiredTypes []parser.Type, autoCommit bool,
) (planNode, error) {
	tracing.AnnotateTrace()

	// This will set the system DB trigger for transactions containing
	// DDL statements that have no effect, such as
	// `BEGIN; INSERT INTO ...; CREATE TABLE IF NOT EXISTS ...; COMMIT;`
	// where the table already exists. This will generate some false
	// refreshes, but that's expected to be quite rare in practice.
	if stmt.StatementType() == parser.DDL {
		p.txn.SetSystemConfigTrigger()
	}

	switch n := stmt.(type) {
	case *parser.AlterTable:
		return p.AlterTable(n)
	case *parser.BeginTransaction:
		return p.BeginTransaction(n)
	case CopyDataBlock:
		return p.CopyData(n, autoCommit)
	case *parser.CopyFrom:
		return p.CopyFrom(n, autoCommit)
	case *parser.CreateDatabase:
		return p.CreateDatabase(n)
	case *parser.CreateIndex:
		return p.CreateIndex(n)
	case *parser.CreateTable:
		return p.CreateTable(n)
	case *parser.CreateUser:
		return p.CreateUser(n)
	case *parser.CreateView:
		return p.CreateView(n)
	case *parser.Delete:
		return p.Delete(n, desiredTypes, autoCommit)
	case *parser.DropDatabase:
		return p.DropDatabase(n)
	case *parser.DropIndex:
		return p.DropIndex(n)
	case *parser.DropTable:
		return p.DropTable(n)
	case *parser.DropView:
		return p.DropView(n)
	case *parser.Explain:
		return p.Explain(n, autoCommit)
	case *parser.Grant:
		return p.Grant(n)
	case *parser.Help:
		return p.Help(n)
	case *parser.Insert:
		return p.Insert(n, desiredTypes, autoCommit)
	case *parser.ParenSelect:
		return p.newPlan(n.Select, desiredTypes, autoCommit)
	case *parser.RenameColumn:
		return p.RenameColumn(n)
	case *parser.RenameDatabase:
		return p.RenameDatabase(n)
	case *parser.RenameIndex:
		return p.RenameIndex(n)
	case *parser.RenameTable:
		return p.RenameTable(n)
	case *parser.Revoke:
		return p.Revoke(n)
	case *parser.Select:
		return p.Select(n, desiredTypes, autoCommit)
	case *parser.SelectClause:
		return p.SelectClause(n, nil, nil, desiredTypes, publicColumns)
	case *parser.Set:
		return p.Set(n)
	case *parser.SetTimeZone:
		return p.SetTimeZone(n)
	case *parser.SetTransaction:
		return p.SetTransaction(n)
	case *parser.SetDefaultIsolation:
		return p.SetDefaultIsolation(n)
	case *parser.Show:
		return p.Show(n)
	case *parser.ShowColumns:
		return p.ShowColumns(n)
	case *parser.ShowConstraints:
		return p.ShowConstraints(n)
	case *parser.ShowCreateTable:
		return p.ShowCreateTable(n)
	case *parser.ShowCreateView:
		return p.ShowCreateView(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.ShowUsers:
		return p.ShowUsers(n)
	case *parser.Split:
		return p.Split(n)
	case *parser.Truncate:
//.........這裏部分代碼省略.........

// newPlan constructs a planNode from a statement. This is used
// recursively by the various node constructors.
func (p *planner) newPlan(
	stmt parser.Statement, desiredTypes []parser.Type, autoCommit bool,
) (planNode, error) {
	tracing.AnnotateTrace()

	// This will set the system DB trigger for transactions containing
	// DDL statements that have no effect, such as
	// `BEGIN; INSERT INTO ...; CREATE TABLE IF NOT EXISTS ...; COMMIT;`
	// where the table already exists. This will generate some false
	// refreshes, but that's expected to be quite rare in practice.
	if stmt.StatementType() == parser.DDL {
		p.txn.SetSystemConfigTrigger()
	}

	// TODO(dan): This iteration makes the plan dispatch no longer constant
	// time. We could fix that with a map of `reflect.Type` but including
	// reflection in such a primary codepath is unfortunate. Instead, the
	// upcoming IR work will provide unique numeric type tags, which will
	// elegantly solve this.
	for _, planHook := range planHooks {
		if fn, header, err := planHook(p.ctx(), stmt, p.execCfg); err != nil {
			return nil, err
		} else if fn != nil {
			return &hookFnNode{f: fn, header: header}, nil
		}
	}

	switch n := stmt.(type) {
	case *parser.AlterTable:
		return p.AlterTable(n)
	case *parser.BeginTransaction:
		return p.BeginTransaction(n)
	case CopyDataBlock:
		return p.CopyData(n, autoCommit)
	case *parser.CopyFrom:
		return p.CopyFrom(n, autoCommit)
	case *parser.CreateDatabase:
		return p.CreateDatabase(n)
	case *parser.CreateIndex:
		return p.CreateIndex(n)
	case *parser.CreateTable:
		return p.CreateTable(n)
	case *parser.CreateUser:
		return p.CreateUser(n)
	case *parser.CreateView:
		return p.CreateView(n)
	case *parser.Delete:
		return p.Delete(n, desiredTypes, autoCommit)
	case *parser.DropDatabase:
		return p.DropDatabase(n)
	case *parser.DropIndex:
		return p.DropIndex(n)
	case *parser.DropTable:
		return p.DropTable(n)
	case *parser.DropView:
		return p.DropView(n)
	case *parser.Explain:
		return p.Explain(n, autoCommit)
	case *parser.Grant:
		return p.Grant(n)
	case *parser.Help:
		return p.Help(n)
	case *parser.Insert:
		return p.Insert(n, desiredTypes, autoCommit)
	case *parser.ParenSelect:
		return p.newPlan(n.Select, desiredTypes, autoCommit)
	case *parser.RenameColumn:
		return p.RenameColumn(n)
	case *parser.RenameDatabase:
		return p.RenameDatabase(n)
	case *parser.RenameIndex:
		return p.RenameIndex(n)
	case *parser.RenameTable:
		return p.RenameTable(n)
	case *parser.Revoke:
		return p.Revoke(n)
	case *parser.Select:
		return p.Select(n, desiredTypes, autoCommit)
	case *parser.SelectClause:
		return p.SelectClause(n, nil, nil, desiredTypes, publicColumns)
	case *parser.Set:
		return p.Set(n)
	case *parser.SetTimeZone:
		return p.SetTimeZone(n)
	case *parser.SetTransaction:
		return p.SetTransaction(n)
	case *parser.SetDefaultIsolation:
		return p.SetDefaultIsolation(n)
	case *parser.Show:
		return p.Show(n)
	case *parser.ShowColumns:
		return p.ShowColumns(n)
	case *parser.ShowConstraints:
		return p.ShowConstraints(n)
	case *parser.ShowCreateTable:
		return p.ShowCreateTable(n)
	case *parser.ShowCreateView:
		return p.ShowCreateView(n)
//.........這裏部分代碼省略.........