60 lines
1.5 KiB
Go
60 lines
1.5 KiB
Go
// Copyright © 2016 Abcum Ltd
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
//
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
|
|
package sql
|
|
|
|
func (p *parser) parseLetStatement() (stmt *LetStatement, err error) {
|
|
|
|
stmt = &LetStatement{}
|
|
|
|
if stmt.KV, stmt.NS, stmt.DB, err = p.o.get(AuthNO); err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
// The first part of a LET expression must
|
|
// always be an identifier, specifying a
|
|
// variable name to set.
|
|
|
|
stmt.Name, err = p.parseIdent()
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
// The next query part must always be a =
|
|
// operator, as this is a LET expression
|
|
// and not a binary expression.
|
|
|
|
_, _, err = p.shouldBe(EQ)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
// The next query part can be any expression
|
|
// including a parenthesised expression or a
|
|
// binary expression so handle accordingly.
|
|
|
|
stmt.What, err = p.parseExpr()
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
// If this query has any subqueries which
|
|
// need to alter the database then mark
|
|
// this query as a writeable statement.
|
|
|
|
stmt.RW = p.buf.rw
|
|
|
|
return
|
|
|
|
}
|