loadwallet "filename"

*bitcoin-cli help loadwallet

loadwallet "filename" ( load_on_startup )

Loads a wallet from a wallet file or directory.
Note that all wallet command-line options used when starting bitcoind will be
applied to the new wallet.

Arguments:
1. filename           (string, required) The wallet directory or .dat file.
2. load_on_startup    (boolean, optional) Save wallet name to persistent settings and load on startup. True to add wallet to startup list, false to remove, null to leave unchanged.

Result:
{                       (json object)
  "name" : "str",       (string) The wallet name if loaded successfully.
  "warning" : "str"     (string) Warning message if wallet was not loaded cleanly.
}

Examples:
> bitcoin-cli loadwallet "test.dat"
> curl --user myusername --data-binary '{"jsonrpc": "1.0", "id": "curltest", "method": "loadwallet", "params": ["test.dat"]}' -H 'content-type: text/plain;' http://127.0.0.1:8332/