github.com/dolthub/go-mysql-server@v0.18.0/sql/plan/show_indexes.go (about)

     1  // Copyright 2020-2021 Dolthub, Inc.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package plan
    16  
    17  import (
    18  	"fmt"
    19  
    20  	"github.com/dolthub/go-mysql-server/sql"
    21  	"github.com/dolthub/go-mysql-server/sql/types"
    22  )
    23  
    24  // ShowIndexes is a node that shows the indexes on a table.
    25  type ShowIndexes struct {
    26  	UnaryNode
    27  	IndexesToShow []sql.Index
    28  }
    29  
    30  // NewShowIndexes creates a new ShowIndexes node. The node must represent a table.
    31  func NewShowIndexes(table sql.Node) *ShowIndexes {
    32  	return &ShowIndexes{
    33  		UnaryNode: UnaryNode{table},
    34  	}
    35  }
    36  
    37  var _ sql.Node = (*ShowIndexes)(nil)
    38  var _ sql.CollationCoercible = (*ShowIndexes)(nil)
    39  
    40  // WithChildren implements the Node interface.
    41  func (n *ShowIndexes) WithChildren(children ...sql.Node) (sql.Node, error) {
    42  	if len(children) != 1 {
    43  		return nil, sql.ErrInvalidChildrenNumber.New(n, len(children), 1)
    44  	}
    45  
    46  	return &ShowIndexes{
    47  		UnaryNode:     UnaryNode{children[0]},
    48  		IndexesToShow: n.IndexesToShow,
    49  	}, nil
    50  }
    51  
    52  // CheckPrivileges implements the interface sql.Node.
    53  func (n *ShowIndexes) CheckPrivileges(ctx *sql.Context, opChecker sql.PrivilegedOperationChecker) bool {
    54  	//TODO: figure out what privileges are required
    55  	return true
    56  }
    57  
    58  // CollationCoercibility implements the interface sql.CollationCoercible.
    59  func (*ShowIndexes) CollationCoercibility(ctx *sql.Context) (collation sql.CollationID, coercibility byte) {
    60  	return sql.Collation_binary, 7
    61  }
    62  
    63  // String implements the fmt.Stringer interface.
    64  func (n *ShowIndexes) String() string {
    65  	return fmt.Sprintf("ShowIndexes(%s)", n.Child)
    66  }
    67  
    68  func (n *ShowIndexes) IsReadOnly() bool {
    69  	return true
    70  }
    71  
    72  // Schema implements the Node interface.
    73  func (n *ShowIndexes) Schema() sql.Schema {
    74  	return sql.Schema{
    75  		&sql.Column{Name: "Table", Type: types.LongText},
    76  		&sql.Column{Name: "Non_unique", Type: types.Int32},
    77  		&sql.Column{Name: "Key_name", Type: types.LongText},
    78  		&sql.Column{Name: "Seq_in_index", Type: types.Int32},
    79  		&sql.Column{Name: "Column_name", Type: types.LongText, Nullable: true},
    80  		&sql.Column{Name: "Collation", Type: types.LongText, Nullable: true},
    81  		&sql.Column{Name: "Cardinality", Type: types.Int64},
    82  		&sql.Column{Name: "Sub_part", Type: types.Int64, Nullable: true},
    83  		&sql.Column{Name: "Packed", Type: types.LongText, Nullable: true},
    84  		&sql.Column{Name: "Null", Type: types.LongText},
    85  		&sql.Column{Name: "Index_type", Type: types.LongText},
    86  		&sql.Column{Name: "Comment", Type: types.LongText},
    87  		&sql.Column{Name: "Index_comment", Type: types.LongText},
    88  		&sql.Column{Name: "Visible", Type: types.LongText},
    89  		&sql.Column{Name: "Expression", Type: types.LongText, Nullable: true},
    90  	}
    91  }