This is all a bit weird.

```
-------------------------------------------------------------------------------

### Versions ###

$ node --version
v0.10.21

$ npm --version
1.3.11

-------------------------------------------------------------------------------

### Doesn't Install Version Explicitly Asked For ###

$ grep mysql package.json 
    "mysql": "2.0.0-alpha9",

$ npm install

$ 

-------------------------------------------------------------------------------

### Greater Than (not expected to work) ###

$ grep mysql package.json 
    "mysql": ">=2.0.0",

$ npm install
npm http GET https://registry.npmjs.org/mysql
npm http 304 https://registry.npmjs.org/mysql
npm ERR! Error: No compatible version found: mysql@'>=2.0.0'
npm ERR! Valid install targets:
npm ERR! ["2.0.0-alpha","2.0.0-alpha2","0.1.0","0.2.0","0.3.0","0.4.0","0.5.0","0.6.0","0.7.0","0.8.0","0.9.0","0.9.1","0.9.2","0.9.3","0.9.4","0.9.5","0.9.6","2.0.0-alpha","2.0.0-alpha2","2.0.0-alpha3","2.0.0-alpha4","2.0.0-alpha5","2.0.0-alpha6","2.0.0-alpha7","2.0.0-alpha8","2.0.0-alpha9"]

$

-------------------------------------------------------------------------------

### Says "Less than or equal to. In this case, prerelease versions ARE allowed" ###

$ grep mysql package.json 
    "mysql": "<=2.0.0",

$ npm install

$

-------------------------------------------------------------------------------

### Says "When using tilde operators, prerelease versions are supported" ###

$ grep mysql package.json 
    "mysql": "~2.0.0",

$ npm install

$ 

-------------------------------------------------------------------------------

### Try being explicit, installs fine, but package.json still doesn't work ###

$ npm install --save mysql@2.0.0-alpha9
npm http GET https://registry.npmjs.org/mysql/2.0.0-alpha9
npm http 304 https://registry.npmjs.org/mysql/2.0.0-alpha9
npm http GET https://registry.npmjs.org/require-all/0.0.3
npm http GET https://registry.npmjs.org/bignumber.js/1.0.1
npm http 304 https://registry.npmjs.org/require-all/0.0.3
npm http 200 https://registry.npmjs.org/bignumber.js/1.0.1
npm http GET https://registry.npmjs.org/bignumber.js/-/bignumber.js-1.0.1.tgz
npm http 200 https://registry.npmjs.org/bignumber.js/-/bignumber.js-1.0.1.tgz
mysql@2.0.0-alpha9 node_modules/mysql
├── require-all@0.0.3
└── bignumber.js@1.0.1

$ grep mysql package.json 
    "mysql": "~2.0.0-alpha9",

$ rm -rf node_modules/mysql

$ npm install

$

-------------------------------------------------------------------------------
```