github.com/dolthub/go-mysql-server@v0.18.0/sql/analyzer/describe.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 analyzer
    16  
    17  import (
    18  	"github.com/dolthub/go-mysql-server/sql"
    19  	"github.com/dolthub/go-mysql-server/sql/plan"
    20  	"github.com/dolthub/go-mysql-server/sql/transform"
    21  )
    22  
    23  // resolveDescribeQuery resolves any DescribeQuery nodes by analyzing their child and assigning it back.
    24  func resolveDescribeQuery(ctx *sql.Context, a *Analyzer, n sql.Node, scope *plan.Scope, sel RuleSelector) (sql.Node, transform.TreeIdentity, error) {
    25  	d, ok := n.(*plan.DescribeQuery)
    26  	if !ok {
    27  		return n, transform.SameTree, nil
    28  	}
    29  
    30  	q, _, err := a.analyzeWithSelector(ctx, d.Query(), scope, SelectAllBatches, sel)
    31  	if err != nil {
    32  		return nil, transform.SameTree, err
    33  	}
    34  
    35  	return d.WithQuery(StripPassthroughNodes(q)), transform.NewTree, nil
    36  }