Question

我想通过喜欢查询并尝试这样：

let name = "pp" //apple

let db = openDB()
  do {
      var queryString = "select * from products where name like '%?%' and deleted = 0 order by id desc"
      let rs = try db.executeQuery(queryString, values:[name])
      var arr:Array<Product> = []
      while rs.next() {
      arr.append(parseProductDB(rs))
      }
      closeDB(db)
} catch {
      print("failed: \(error.localizedDescription)")
      closeDB(db)
}

但它不起作用。

Answer 1

试试这个：

let db = openDB()
do {
    var queryString =
    queryString = String(format:"select * from products where name like '%%%@%%' and deleted = 0 order by id desc",name)
    let rs = try db.executeQuery(queryString, values:nil)
    var arr:Array<Product> = []
    while rs.next() {
    arr.append(parseProductDB(rs))
    }
    closeDB(db)

} catch {
            print("failed: \(error.localizedDescription)")
            closeDB(db)
}

Answer 2

只需在sql语句中传递参数？并使用SQL通配符包装传递的值，如下所示：

let name = "%pp%"
...
var queryString = "select * from products where name like ? and deleted = 0 order by id desc"

原因在于SQLite，并且可能在每个其他SQL引擎中，参数是一个包含其值和类型信息的完整实体。因此，永远不需要在{（1）}之类的引号（'）中包装参数，这实际上是错误的做法。另外'%?%'运算符只需要一个字符串表达式作为操作数，如果需要可能包含SQL通配符。因此，您只需要创建一个带有嵌入式通配符（％，_等）的字符串表达式，并在需要时将其传递给您的语句。

希望它有所帮助。

Answer 3

它对我有用（swift 4，Xcode 9）：

let texto_like : String = "%\(texto)%"

let sql = "select * from TABLE where MY_COLUMN like ? COLLATE NOCASE"

如何在FMDB中使用Like with Text查询iOS Swift 4？

3 个答案: