Unlike bind variables, a substitution variable is processed on the client side, and its value will be substituted before submitting the command for execution.

不同于绑定变量，替代变量在客户端加以处理，且其值会在提交执行命令之前被替换。

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Joel Thomas, on in a triple substitution for the home side, then went close to replicating Riordan's earlier heroics but his shot was brilliantly tipped away by Ma-Kalambay.

BBC: Hamilton Accies 0-1 Hibernian

With his side showing no sign of a breakthrough, Le Guen resorted to a double substitution, with Kris Boyd and Chris Burke replacing Dado Prso and Libor Sionko.

BBC: SPORT | Football | Scottish Premier | Dunfermline Ath 1-1 Rangers