Merge pull request #10 from hipeople/replace-into

add support for REPLACE INTO

create.go

@@ -8,19 +8,11 @@ import (
 )
 
 func createAndGetResult(exec ExecFn, record interface{}) (stdsql.Result, error) {
-	row, err := NewRow(record)
+	row, columns, values, err := valuesForRecord(record)
 	if err != nil {
 		return nil, err
 	}
 
-	columns := []string{}
-	values := []interface{}{}
-
-	for c, v := range row.SQLValues() {
-		columns = append(columns, c)
-		values = append(values, v)
-	}
-
 	return exec(sql.InsertQuery(row.SQLTableName, columns), values...)
 }
 
@@ -35,6 +27,50 @@ func createAndRead(exec ExecFn, query QueryFn, record interface{}) error {
 		return err
 	}
 
+	return readLastInsert(query, record, result)
+}
+
+func replaceAndGetResult(exec ExecFn, record interface{}) (stdsql.Result, error) {
+	row, columns, values, err := valuesForRecord(record)
+	if err != nil {
+		return nil, err
+	}
+
+	return exec(sql.ReplaceQuery(row.SQLTableName, columns), values...)
+}
+
+func replace(exec ExecFn, record interface{}) error {
+	_, err := replaceAndGetResult(exec, record)
+	return err
+}
+
+func replaceAndRead(exec ExecFn, query QueryFn, record interface{}) error {
+	result, err := replaceAndGetResult(exec, record)
+	if err != nil {
+		return err
+	}
+
+	return readLastInsert(query, record, result)
+}
+
+func valuesForRecord(record interface{}) (*Row, []string, []interface{}, error) {
+	row, err := NewRow(record)
+	if err != nil {
+		return nil, nil, nil, err
+	}
+
+	columns := []string{}
+	values := []interface{}{}
+
+	for c, v := range row.SQLValues() {
+		columns = append(columns, c)
+		values = append(values, v)
+	}
+
+	return row, columns, values, nil
+}
+
+func readLastInsert(query QueryFn, record interface{}, result stdsql.Result) error {
 	id, err := result.LastInsertId()
 	if err != nil {
 		return err

db.go

@@ -118,6 +118,20 @@ func (db *DB) CreateAndRead(record interface{}) error {
 	return createAndRead(db.Exec, db.Query, record)
 }
 
+// Replaces given record into the database, generating a replace query for it.
+func (db *DB) Replace(record interface{}) error {
+	return replace(db.Exec, record)
+}
+
+func (db *DB) ReplaceAndGetResult(record interface{}) (stdsql.Result, error) {
+	return replaceAndGetResult(db.Exec, record)
+}
+
+// Replaces given record and scans the replaceed row back to the given row.
+func (db *DB) ReplaceAndRead(record interface{}) error {
+	return replaceAndRead(db.Exec, db.Query, record)
+}
+
 // Runs given SQL query and scans the result rows into the given target interface. The target
 // interface could be both a single record or a slice of records.
 //

sql/table.go

@@ -109,17 +109,19 @@ func ShowTablesLikeQuery(name string) string {
 }
 
 func InsertQuery(tableName string, columnNames []string) string {
-	var questionMarks string
-
-	if len(columnNames) > 0 {
-		questionMarks = strings.Repeat("?,", len(columnNames))
-		questionMarks = questionMarks[:len(questionMarks)-1]
-	}
+	questionMarks := repeatComma(len(columnNames), "?")
 
 	return fmt.Sprintf("INSERT INTO %s (%s) VALUES (%s)",
 		tableName, strings.Join(quoteColumnNames(columnNames), ","), questionMarks)
 }
 
+func ReplaceQuery(tableName string, columnNames []string) string {
+	questionMarks := repeatComma(len(columnNames), "?")
+
+	return fmt.Sprintf("REPLACE INTO %s (%s) VALUES (%s)",
+		tableName, strings.Join(quoteColumnNames(columnNames), ","), questionMarks)
+}
+
 func SelectQuery(tableName string, columnNames []string) string {
 	columns := strings.Join(columnNames, ",")
 	if columns == "" {
@@ -150,3 +152,14 @@ func quoteColumnNames(columns []string) []string {
 
 	return quoted
 }
+
+func repeatComma(num int, char string) string {
+	var out string
+
+	if num > 0 {
+		out = strings.Repeat(char+",", num)
+		out = out[:len(out)-1]
+	}
+
+	return out
+}

transaction.go

@@ -51,6 +51,16 @@ func (tx *Tx) CreateAndRead(record interface{}) error {
 	return createAndRead(tx.Exec, tx.Query, record)
 }
 
+// Replace given record to the database.
+func (tx *Tx) Replace(record interface{}) error {
+	return replace(tx.Exec, record)
+}
+
+// Replaces given record and scans the replaceed row back to the given row.
+func (tx *Tx) ReplaceAndRead(record interface{}) error {
+	return replaceAndRead(tx.Exec, tx.Query, record)
+}
+
 // Run a select query on the databaase (w/ given parameters optionally) and scan the result(s) to the
 // target interface specified as the first parameter.
 //