Golang sqlbase.ColumnDescriptor類代碼示例

本文整理匯總了Golang中github.com/cockroachdb/cockroach/sql/sqlbase.ColumnDescriptor類的典型用法代碼示例。如果您正苦於以下問題：Golang ColumnDescriptor類的具體用法？Golang ColumnDescriptor怎麽用？Golang ColumnDescriptor使用的例子？那麽, 這裏精選的類代碼示例或許可以為您提供幫助。

在下文中一共展示了ColumnDescriptor類的3個代碼示例，這些例子默認根據受歡迎程度排序。您可以為喜歡或者感覺有用的代碼點讚，您的評價將有助於係統推薦出更棒的Golang代碼示例。

示例1: RenameColumn

// RenameColumn renames the column.
// Privileges: CREATE on table.
//   notes: postgres requires CREATE on the table.
//          mysql requires ALTER, CREATE, INSERT on the table.
func (p *planner) RenameColumn(n *parser.RenameColumn) (planNode, error) {
	newColName := string(n.NewName)
	if newColName == "" {
		return nil, errEmptyColumnName
	}

	if err := n.Table.NormalizeTableName(p.session.Database); err != nil {
		return nil, err
	}

	dbDesc, err := p.getDatabaseDesc(n.Table.Database())
	if err != nil {
		return nil, err
	}
	if dbDesc == nil {
		return nil, sqlbase.NewUndefinedDatabaseError(n.Table.Database())
	}

	// Check if table exists.
	tbKey := tableKey{dbDesc.ID, n.Table.Table()}.Key()
	gr, err := p.txn.Get(tbKey)
	if err != nil {
		return nil, err
	}
	if !gr.Exists() {
		if n.IfExists {
			// Noop.
			return &emptyNode{}, nil
		}
		// Key does not exist, but we want it to: error out.
		return nil, fmt.Errorf("table %q does not exist", n.Table.Table())
	}

	tableDesc, err := p.getTableDesc(n.Table)
	if err != nil {
		return nil, err
	}
	if tableDesc == nil {
		return nil, sqlbase.NewUndefinedTableError(n.Table.String())
	}

	colName := string(n.Name)
	status, i, err := tableDesc.FindColumnByName(colName)
	// n.IfExists only applies to table, no need to check here.
	if err != nil {
		return nil, err
	}
	var column *sqlbase.ColumnDescriptor
	if status == sqlbase.DescriptorActive {
		column = &tableDesc.Columns[i]
	} else {
		column = tableDesc.Mutations[i].GetColumn()
	}

	if err := p.checkPrivilege(tableDesc, privilege.CREATE); err != nil {
		return nil, err
	}

	if sqlbase.EqualName(colName, newColName) {
		// Noop.
		return &emptyNode{}, nil
	}

	if _, _, err := tableDesc.FindColumnByName(newColName); err == nil {
		return nil, fmt.Errorf("column name %q already exists", newColName)
	}

	preFn := func(expr parser.Expr) (err error, recurse bool, newExpr parser.Expr) {
		if qname, ok := expr.(*parser.QualifiedName); ok {
			if err := qname.NormalizeColumnName(); err != nil {
				return err, false, nil
			}
			if qname.Column() == colName {
				qname.Indirect[0] = parser.NameIndirection(newColName)
				qname.ClearString()
			}
			return nil, false, qname
		}
		return nil, true, expr
	}

	exprStrings := make([]string, len(tableDesc.Checks))
	for i, check := range tableDesc.Checks {
		exprStrings[i] = check.Expr
	}
	exprs, err := parser.ParseExprsTraditional(exprStrings)
	if err != nil {
		return nil, err
	}

	for i := range tableDesc.Checks {
		expr, err := parser.SimpleVisit(exprs[i], preFn)
		if err != nil {
			return nil, err
		}
		if after := expr.String(); after != tableDesc.Checks[i].Expr {
//.........這裏部分代碼省略.........

開發者ID:CubeLite，項目名稱:cockroach，代碼行數:101，代碼來源:rename.go

示例2: RenameColumn

// RenameColumn renames the column.
// Privileges: CREATE on table.
//   notes: postgres requires CREATE on the table.
//          mysql requires ALTER, CREATE, INSERT on the table.
func (p *planner) RenameColumn(n *parser.RenameColumn) (planNode, error) {
	newColName := string(n.NewName)
	if newColName == "" {
		return nil, errEmptyColumnName
	}

	if err := n.Table.NormalizeTableName(p.session.Database); err != nil {
		return nil, err
	}

	dbDesc, err := p.getDatabaseDesc(n.Table.Database())
	if err != nil {
		return nil, err
	}
	if dbDesc == nil {
		return nil, databaseDoesNotExistError(n.Table.Database())
	}

	// Check if table exists.
	tbKey := tableKey{dbDesc.ID, n.Table.Table()}.Key()
	gr, err := p.txn.Get(tbKey)
	if err != nil {
		return nil, err
	}
	if !gr.Exists() {
		if n.IfExists {
			// Noop.
			return &emptyNode{}, nil
		}
		// Key does not exist, but we want it to: error out.
		return nil, fmt.Errorf("table %q does not exist", n.Table.Table())
	}

	tableDesc, err := p.getTableDesc(n.Table)
	if err != nil {
		return nil, err
	}
	if tableDesc == nil {
		return nil, tableDoesNotExistError(n.Table.String())
	}

	colName := string(n.Name)
	status, i, err := tableDesc.FindColumnByName(colName)
	// n.IfExists only applies to table, no need to check here.
	if err != nil {
		return nil, err
	}
	var column *sqlbase.ColumnDescriptor
	if status == sqlbase.DescriptorActive {
		column = &tableDesc.Columns[i]
	} else {
		column = tableDesc.Mutations[i].GetColumn()
	}

	if err := p.checkPrivilege(tableDesc, privilege.CREATE); err != nil {
		return nil, err
	}

	if sqlbase.EqualName(colName, newColName) {
		// Noop.
		return &emptyNode{}, nil
	}

	if _, _, err := tableDesc.FindColumnByName(newColName); err == nil {
		return nil, fmt.Errorf("column name %q already exists", newColName)
	}

	// Rename the column in the indexes.
	renameColumnInIndex := func(idx *sqlbase.IndexDescriptor) {
		for i, id := range idx.ColumnIDs {
			if id == column.ID {
				idx.ColumnNames[i] = newColName
			}
		}
	}
	for i := range tableDesc.Indexes {
		renameColumnInIndex(&tableDesc.Indexes[i])
	}
	for _, m := range tableDesc.Mutations {
		if idx := m.GetIndex(); idx != nil {
			renameColumnInIndex(idx)
		}
	}
	column.Name = newColName
	if err := tableDesc.SetUpVersion(); err != nil {
		return nil, err
	}

	descKey := sqlbase.MakeDescMetadataKey(tableDesc.GetID())
	if err := tableDesc.Validate(); err != nil {
		return nil, err
	}
	if err := p.txn.Put(descKey, sqlbase.WrapDescriptor(tableDesc)); err != nil {
		return nil, err
	}
	p.notifySchemaChange(tableDesc.ID, sqlbase.InvalidMutationID)
//.........這裏部分代碼省略.........

開發者ID:GitGoldie，項目名稱:cockroach，代碼行數:101，代碼來源:rename.go

示例3: RenameColumn

// RenameColumn renames the column.
// Privileges: CREATE on table.
//   notes: postgres requires CREATE on the table.
//          mysql requires ALTER, CREATE, INSERT on the table.
func (p *planner) RenameColumn(n *parser.RenameColumn) (planNode, error) {
	// Check if table exists.
	tn, err := n.Table.NormalizeWithDatabaseName(p.session.Database)
	if err != nil {
		return nil, err
	}
	tableDesc, err := p.getTableDesc(tn)
	if err != nil {
		return nil, err
	}
	if tableDesc == nil {
		if n.IfExists {
			// Noop.
			return &emptyNode{}, nil
		}
		// Key does not exist, but we want it to: error out.
		return nil, fmt.Errorf("table %q does not exist", tn.Table())
	}

	if err := p.checkPrivilege(tableDesc, privilege.CREATE); err != nil {
		return nil, err
	}

	if n.NewName == "" {
		return nil, errEmptyColumnName
	}
	normNewColName := sqlbase.NormalizeName(n.NewName)
	normColName := sqlbase.NormalizeName(n.Name)

	status, i, err := tableDesc.FindColumnByNormalizedName(normColName)
	// n.IfExists only applies to table, no need to check here.
	if err != nil {
		return nil, err
	}
	var column *sqlbase.ColumnDescriptor
	if status == sqlbase.DescriptorActive {
		column = &tableDesc.Columns[i]
	} else {
		column = tableDesc.Mutations[i].GetColumn()
	}

	if normColName == normNewColName {
		// Noop.
		return &emptyNode{}, nil
	}

	if _, _, err := tableDesc.FindColumnByNormalizedName(normNewColName); err == nil {
		return nil, fmt.Errorf("column name %q already exists", n.NewName)
	}

	preFn := func(expr parser.Expr) (err error, recurse bool, newExpr parser.Expr) {
		if vBase, ok := expr.(parser.VarName); ok {
			v, err := vBase.NormalizeVarName()
			if err != nil {
				return err, false, nil
			}
			if c, ok := v.(*parser.ColumnItem); ok {
				if sqlbase.NormalizeName(c.ColumnName) == normColName {
					c.ColumnName = n.NewName
				}
			}
			return nil, false, v
		}
		return nil, true, expr
	}

	exprStrings := make([]string, len(tableDesc.Checks))
	for i, check := range tableDesc.Checks {
		exprStrings[i] = check.Expr
	}
	exprs, err := parser.ParseExprsTraditional(exprStrings)
	if err != nil {
		return nil, err
	}

	for i := range tableDesc.Checks {
		expr, err := parser.SimpleVisit(exprs[i], preFn)
		if err != nil {
			return nil, err
		}
		if after := expr.String(); after != tableDesc.Checks[i].Expr {
			tableDesc.Checks[i].Expr = after
		}
	}
	// Rename the column in the indexes.
	tableDesc.RenameColumnNormalized(column.ID, normNewColName)
	column.Name = normNewColName
	if err := tableDesc.SetUpVersion(); err != nil {
		return nil, err
	}

	descKey := sqlbase.MakeDescMetadataKey(tableDesc.GetID())
	if err := tableDesc.Validate(p.txn); err != nil {
		return nil, err
	}
	if err := p.txn.Put(descKey, sqlbase.WrapDescriptor(tableDesc)); err != nil {
//.........這裏部分代碼省略.........

開發者ID:yangxuanjia，項目名稱:cockroach，代碼行數:101，代碼來源:rename.go

注：本文中的github.com/cockroachdb/cockroach/sql/sqlbase.ColumnDescriptor類示例由純淨天空整理自Github/MSDocs等開源代碼及文檔管理平台，相關代碼片段篩選自各路編程大神貢獻的開源項目，源碼版權歸原作者所有，傳播和使用請參考對應項目的License；未經允許，請勿轉載。