delete query parser

main.go

@@ -56,30 +56,47 @@ func main() {
 	// fmt.Println(qu.Where)
 	// return
 
+	// ParserService := parser.New()
+	// q, err := ParserService.ParseQuery([]byte(`
+	// 	INSERT_INTO testtable (firstname,lastname)
+	// 	VALUES
+	// 		("Vahag","Zargaryan"),
+	// 		("Ruben", "Manandyan"),
+	// 		("Sergey", "Zargaryan"),
+	// 		("Arman", "Sargsyan"),
+	// 		("Mery", "Voskanyan"),
+	// 		("David", "Harutyunyan"),
+	// 		("Alexader", "Bakunc"),
+	// 		("Hayk", "Vardanyan"),
+	// 		("Serob", "Gevorgyan"),
+	// 		("Gevorg", "Aznauryan");
+	// `))
+	// if err != nil {
+	// 	fmt.Println(err)
+	// 	os.Exit(1)
+	// }
+	// qu := q.(*dml.QueryInsert)
+	// fmt.Println(qu.Type)
+	// fmt.Println(qu.Table)
+	// fmt.Println(qu.Columns)
+	// fmt.Println(qu.Values)
+	// return
+
 	ParserService := parser.New()
 	q, err := ParserService.ParseQuery([]byte(`
-		INSERT testtable (firstname,lastname)
-		VALUES
-			("Vahag","Zargaryan"),
-			("Ruben", "Manandyan"),
-			("Sergey", "Zargaryan"),
-			("Arman", "Sargsyan"),
-			("Mery", "Voskanyan"),
-			("David", "Harutyunyan"),
-			("Alexader", "Bakunc"),
-			("Hayk", "Vardanyan"),
-			("Serob", "Gevorgyan"),
-			("Gevorg", "Aznauryan");
+		DELETE_FROM testtable
+		WHERE_INDEX id_1 id >= 100 AND id < 800
+		WHERE id > 10 AND (firstname = "Vahag" OR lastname = "Sargsyan");
 	`))
 	if err != nil {
 		fmt.Println(err)
 		os.Exit(1)
 	}
-	qu := q.(*dml.QueryInsert)
+	qu := q.(*dml.QueryDelete)
 	fmt.Println(qu.Type)
 	fmt.Println(qu.Table)
-	fmt.Println(qu.Columns)
-	fmt.Println(qu.Values)
+	fmt.Println(qu.WhereIndex)
+	fmt.Println(qu.Where)
 	return
 
 	pwd, _ := os.Getwd()

services/parser/query/dml/delete.go

@@ -1,8 +1,10 @@
 package dml
 
 import (
+	"encoding/json"
 	"text/scanner"
 
+	"go-dbms/pkg/types"
 	"go-dbms/services/parser/query"
 )
 
@@ -14,6 +16,98 @@ type QueryDelete struct {
 	WhereIndex *whereIndex `json:"where_index"`
 }
 
-func (qs *QueryDelete) Parse(s *scanner.Scanner) (err error) {
+func (qd *QueryDelete) Parse(s *scanner.Scanner) (err error) {
+	defer func ()  {
+		if r := recover(); r != nil {
+			var ok bool
+			err, ok = r.(error)
+			if !ok {
+				panic(r)
+			}
+		}
+	}()
+
+	qd.Type = query.DELETE
+
+	qd.parseFrom(s)
+
+	word := s.TokenText()
+	if word == "WHERE_INDEX" {
+		qd.parseWhereIndex(s)
+	}
+
+	word = s.TokenText()
+	if word == "WHERE" {
+		qd.parseWhere(s)
+	}
+
 	return nil
 }
+
+func (qd *QueryDelete) parseFrom(s *scanner.Scanner) {
+	tok := s.Scan()
+	word := s.TokenText()
+	_, isKW := keyWords[word]
+	if tok == scanner.EOF {
+		panic(ErrSyntax)
+	} else if isKW {
+		panic(ErrNoFrom)
+	}
+
+	qd.Table = word
+
+	tok = s.Scan()
+	word = s.TokenText()
+	_, idKW := keyWords[word]
+	if tok != scanner.EOF && !idKW {
+		panic(ErrSyntax)
+	}
+}
+
+func (qs *QueryDelete) parseWhereIndex(s *scanner.Scanner) {
+	tok := s.Scan()
+	word := s.TokenText()
+	_, isKW := keyWords[word]
+	if tok == scanner.EOF || isKW {
+		panic(ErrSyntax)
+	}
+
+	qs.WhereIndex = &whereIndex{}
+	qs.WhereIndex.Name = word
+	qs.WhereIndex.FilterStart = &indexFilter{}
+	col, op, val := parseWhereFilter(s, false)
+	var valInt interface{}
+	if err := json.Unmarshal([]byte(val), &valInt); err != nil {
+		panic(err)
+	}
+	qs.WhereIndex.FilterStart.Operator = op
+	qs.WhereIndex.FilterStart.Value = map[string]types.DataType{
+		col: types.ParseJSONValue(valInt),
+	}
+
+	tok = s.Scan()
+	word = s.TokenText()
+	_, isKW = keyWords[word]
+	if tok == scanner.EOF || isKW {
+		panic(ErrSyntax)
+	}
+
+	if word == "AND" {
+		qs.WhereIndex.FilterEnd = &indexFilter{}
+		col, op, val := parseWhereFilter(s, false)
+		var valInt interface{}
+		if err := json.Unmarshal([]byte(val), &valInt); err != nil {
+			panic(err)
+		}
+		qs.WhereIndex.FilterEnd.Operator = op
+		qs.WhereIndex.FilterEnd.Value = map[string]types.DataType{
+			col: types.ParseJSONValue(valInt),
+		}
+	}
+
+	s.Scan()
+}
+
+func (qs *QueryDelete) parseWhere(s *scanner.Scanner) {
+	qs.Where = (*where)(parseWhere(s))
+}

services/parser/query/dml/dml.go

@@ -15,7 +15,7 @@ func Parse(s *scanner.Scanner, queryType query.QueryType) (query.Querier, error)
 	var q query.Querier
 
 	switch queryType {
-		// case query.DELETE: q = &QueryDelete{}
+		case query.DELETE: q = &QueryDelete{}
 		case query.INSERT: q = &QueryInsert{}
 		case query.SELECT: q = &QuerySelect{}
 		// case query.UPDATE: q = &QueryUpdate{}

services/parser/query/dml/key_words.go

@@ -10,8 +10,10 @@ var keyWords = map[string]struct{}{
 	"ORDER_BY":    {},
 	"LIMIT":       {},
 
-	"INSERT": {},
-	"VALUES": {},
+	"INSERT_INTO": {},
+	"VALUES":      {},
+
+	"DELETE_FROM": {},
 }
 
 var indexOperators = map[string]struct{}{

services/parser/query/query.go

@@ -5,10 +5,10 @@ import "text/scanner"
 type QueryType string
 
 const (
-	INSERT   QueryType = "INSERT"
+	INSERT   QueryType = "INSERT_INTO"
 	SELECT   QueryType = "SELECT"
 	UPDATE   QueryType = "UPDATE"
-	DELETE   QueryType = "DELETE"
+	DELETE   QueryType = "DELETE_FROM"
 	CREATE   QueryType = "CREATE"
 	ALTER    QueryType = "ALTER"
 	DROP     QueryType = "DROP"