jsp - How to escape parentheses in jsp

Question

I keep getting errors on this line of code:

pstmt = conn.prepareStatement( "SELECT * FROM products WHERE category IN" +
"(" + "SELECT catid FROM category WHERE name= currentcat " + ")" );

I'm guessing the problem is my parentheses. If it's not then what's wrong with my code? Thank you!

Answer 1

它与括号无关。在 SQL 中，varchar 值必须用单引号括起来：

SELECT catid FROM category WHERE name = 'currentcat'

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