数据库删除数据出错delphi

with data_m.ADO_aaa do
begin
close;
sql.Clear;
sql.add('delete from aaa where ddd='dd'');
execsql;
end;

with data_m.ADO_aaa do
begin
close;
sql.Clear;
sql.add('delete from aaa where ddd=''dd''');
execsql;
end;

单引号在编译的时候 如果是一个的话 编译器认为他是字符串开始从字符单引号之后的那个字符开始才是字符串的内容；

with data_m.ADO_aaa do begin close; sql.sql.commandtext='delete from aaa where ddd='dd''; execsql; end;

sql.add('delete from aaa where ddd='dd'');

你的句子写错了，应该改成

sql.add('delete from aaa where ddd=''dd''');