Once and for all: Rails migrations integer :limit option

| Posted: | ~100wrds (~1min) | Last updated:
| Tagged mysql ruby on rails rails sql migrations integer limit

I literally always have to look up the meaning of :limit in migrations when it comes to integer values. Here’s an overview. Now let’s memorise it (oh, this works for MySQL, other databases may work differently):

:limit Numeric Type Column Size Max value
1 tinyint 1 byte 127
2 smallint 2 bytes 32767
3 mediumint 3 byte 8388607
nil, 4, 11 int(11) 4 byte 2147483647
5..8 bigint 8 byte 9223372036854775807

Note: by default MySQL uses signed integers and Rails has no way (that I know of) to change this behaviour. Subsequently, the max. values noted are for signed integers.

My site is free of ads and trackers. I record privacy-respecting usage statistics with Fathom.

Was this post helpful to you? Why not ☕ Buy me a coffee.