I have a simple web app , and want to save some numbers of Float or Double format in SQL server.
but there is a problem , when I try to save 123.66 , In Table I see
You're not actually trying to save 123.66, because you can't represent 123.66 exactly as a float or double. The database is saving the data more accurately than you're used to, that's all.
If you want to save decimal numbers accurately, use the decimal type.
See my articles on floating binary point and floating decimal point types for more info.