[英]How to handle the multiple threads with FMDB Using SQLite In IOS Swift
[英]How to using Like with Text in FMDB query iOS Swift 4?
我想用like查詢並嘗試這樣:
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。
試試這個:
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)
}
它對我有用(swift 4,Xcode 9):
let texto_like : String = "%\(texto)%"
let sql = "select * from TABLE where MY_COLUMN like ? COLLATE NOCASE"
只需在您的 SQL 語句中傳遞參數?
並用 SQL 通配符包裝您傳遞的值,如下所示:
let name = "%pp%"
...
var queryString = "select * from products where name like ? and deleted = 0 order by id desc"
原因是在 SQLite 中,並且可能在所有其他 SQL 引擎中,參數是一個完整的實體,包括其值和類型信息。 因此,像'%?%'
這樣'%?%'
引號 (') 中的參數從不需要,實際上是錯誤的做法。
同樣like
操作符只需要一個字符串表達式,因為它的操作數可能包含 SQL 通配符(如果需要)。 因此,您只需要創建一個帶有嵌入通配符(%、_ 等)的字符串表達式,並在需要時將其傳遞給您的語句。
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