构造SQL语句时，插值(使用{}弯曲括号)和串联(.或点)之间的区别 [英] Difference between interpolation (using {} squiggly brackets) and concatenation (., or dot) when constructing an SQL statement

问题描述

有什么区别:

$sql = "select * from {$table}";

和这个:

$sql = "select * from ".$table; 

有什么区别吗?

推荐答案

除了使用串联和不使用串联外，没有什么区别.

There isn't much of a difference other than one uses concatenation and one doesn't.

您也可以将其写为

$sql = "select * from $table";

您也可以在字符串中使用{}来引用对象.

You can use {} in your string to refer to objects as well.

如果表是名称或数组

$sql = "select * from {$table->name}"; //works
$sql = "select * from $table->name"; //works too
$sql = "select * from $table->innerTable->table"; //doesn't work

$sql = "select * from {$table['name']}"; //works
$sql = "select * from $table['name']"; //breaks

我个人使用它来提高可读性，因为我总是知道我在指的是变量.

I personally use it to increase readability, because I'll always know I'm referring to a variable.

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