What is {} in the SQL query? $ Sqlstrselect & nbsp; name & nbsp; from & nbsp; user & nbsp; where & nbsp; the code I wrote. what is the role of {} in it? Thank you ~~ ------ Solution ------------------ in the string, {variable} is used to indicate the value of a variable. what is {} in the SQL query?
$ Sqlstr = "select name from user where id = '{$ row [0]}'";
What is the role of {} in the code I wrote?
Thank you ~~
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In the string "", {variable} is used to reference the value of a variable. of course, it can be used normally without adding brackets in most cases, but it is a good habit to add braces.
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The content enclosed by braces "{}" indicates a whole.
Anything that may be ambiguous should be enclosed in curly brackets "{}".
For example, multiple lines of code in your sample code and condition statement branch, etc.
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{} Is actually a block, a whole.
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It is declared that this is a variable, because sometimes "" and ''will encounter errors, which avoids
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This is basically used to enclose variables, which can be safely used as real variables in strings.
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This has nothing to do with SQL. you have explained the role upstairs.
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It seems that there is little relationship.
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The difference is not big. one is to repair the house without a security helmet, and the other is to repair the house with a security helmet !!
