spanner/spansql: parseDDL does not support GENERATE_UUID

[egonvb]

	sql := "CREATE TABLE Test ( " +
		"Id STRING(36) NOT NULL DEFAULT( GENERATE_UUID() )" +
		") PRIMARY KEY (Id);"
	ddl, err := spansql.ParseDDL("", string(sql))

results in following error

err :1.65: got "(" while expecting ")"

The parser looks unable to handle the generate_uuid function as default for the column.

[rahul2393]

Hello @egonvb, we already have a fix in pipeline to be released in 1.50.0 #8482.