Accessing an SQLite Database in Swift

2019-01-02 17:21发布

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问题:

I'm looking for a way to access an SQLite database in my app with Swift code.

I know that I can use an SQLite Wrapper in Objective C and use the bridging header, but I'd rather be able to do this project entirely in Swift. Is there a way to do this, if so, can someone point me to a reference that shows how to submit a query, retrieve rows, etc?

回答1:

While you should probably use one of the many SQLite wrappers (I prefer FMDB, myself), if you wanted to know how to call the SQLite library yourself, you would:

Configure your Swift project to handle SQLite C calls. If using Xcode 9, you can simply do:
```
import SQLite3
```
In earlier versions of Xcode, you can:
- Create bridging header file to the project. See the Importing Objective-C into Swift section of the Using Swift with Cocoa and Objective-C. This bridging header should import sqlite3.h:
```
#import <sqlite3.h>
```
- Add the libsqlite3.tbd (or for even older versions, the libsqlite3.dylib) to your project:

Create/open database.

let fileURL = try! FileManager.default.url(for: .documentDirectory, in: .userDomainMask, appropriateFor: nil, create: false)
    .appendingPathComponent("test.sqlite")

// open database

var db: OpaquePointer?
if sqlite3_open(fileURL.path, &db) != SQLITE_OK {
    print("error opening database")
}

Use sqlite3_exec to perform SQL (e.g. create table).

if sqlite3_exec(db, "create table if not exists test (id integer primary key autoincrement, name text)", nil, nil, nil) != SQLITE_OK {
    let errmsg = String(cString: sqlite3_errmsg(db)!)
    print("error creating table: \(errmsg)")
}

Use sqlite3_prepare_v2 to prepare SQL with ? placeholder to which we'll bind value.

var statement: OpaquePointer?

if sqlite3_prepare_v2(db, "insert into test (name) values (?)", -1, &statement, nil) != SQLITE_OK {
    let errmsg = String(cString: sqlite3_errmsg(db)!)
    print("error preparing insert: \(errmsg)")
}

if sqlite3_bind_text(statement, 1, "foo", -1, SQLITE_TRANSIENT) != SQLITE_OK {
    let errmsg = String(cString: sqlite3_errmsg(db)!)
    print("failure binding foo: \(errmsg)")
}

if sqlite3_step(statement) != SQLITE_DONE {
    let errmsg = String(cString: sqlite3_errmsg(db)!)
    print("failure inserting foo: \(errmsg)")
}

Note, that uses the SQLITE_TRANSIENT constant which can be implemented as follows:

internal let SQLITE_STATIC = unsafeBitCast(0, to: sqlite3_destructor_type.self)
internal let SQLITE_TRANSIENT = unsafeBitCast(-1, to: sqlite3_destructor_type.self)

Reset SQL to insert another value. In this example, I'll insert a NULL value:

if sqlite3_reset(statement) != SQLITE_OK {
    let errmsg = String(cString: sqlite3_errmsg(db)!)
    print("error resetting prepared statement: \(errmsg)")
}

if sqlite3_bind_null(statement, 1) != SQLITE_OK {
    let errmsg = String(cString: sqlite3_errmsg(db)!)
    print("failure binding null: \(errmsg)")
}

if sqlite3_step(statement) != SQLITE_DONE {
    let errmsg = String(cString: sqlite3_errmsg(db)!)
    print("failure inserting null: \(errmsg)")
}

Finalize prepared statement to recover memory associated with that prepared statement:

if sqlite3_finalize(statement) != SQLITE_OK {
    let errmsg = String(cString: sqlite3_errmsg(db)!)
    print("error finalizing prepared statement: \(errmsg)")
}

statement = nil

Prepare new statement for selecting values from table and loop through retrieving the values:

if sqlite3_prepare_v2(db, "select id, name from test", -1, &statement, nil) != SQLITE_OK {
    let errmsg = String(cString: sqlite3_errmsg(db)!)
    print("error preparing select: \(errmsg)")
}

while sqlite3_step(statement) == SQLITE_ROW {
    let id = sqlite3_column_int64(statement, 0)
    print("id = \(id); ", terminator: "")

    if let cString = sqlite3_column_text(statement, 1) {
        let name = String(cString: cString)
        print("name = \(name)")
    } else {
        print("name not found")
    }
}

if sqlite3_finalize(statement) != SQLITE_OK {
    let errmsg = String(cString: sqlite3_errmsg(db)!)
    print("error finalizing prepared statement: \(errmsg)")
}

statement = nil

Close database:

if sqlite3_close(db) != SQLITE_OK {
    print("error closing database")
}

db = nil

For Swift 2, see previous revision of this answer.

回答2:

The best you can do is import the dynamic library inside a bridging header:

Add libsqlite3.dylib to your "Link Binary With Libraries" build phase
Create a "Bridging-Header.h" and add #import <sqlite3.h> to the top
set "Bridging-Header.h" for the "Objective-C Bridging Header" setting in Build Settings under "Swift Compiler - Code Generation"

You will then be able to access all of the c methods like sqlite3_open from your swift code.

However, you may just want to use FMDB and import that through the bridging header as that is a more object oriented wrapper of sqlite. Dealing with C pointers and structs will be cumbersome in Swift.

回答3:

I too was looking for some way to interact with SQLite the same way I was used to doing previously in Objective-C. Admittedly, because of C compatibility, I just used the straight C API.

As no wrapper currently exists for SQLite in Swift and the SQLiteDB code mentioned above goes a bit higher level and assumes certain usage, I decided to create a wrapper and get a bit familiar with Swift in the process. You can find it here: https://github.com/chrismsimpson/SwiftSQLite.

var db = SQLiteDatabase();
db.open("/path/to/database.sqlite");

var statement = SQLiteStatement(database: db);

if ( statement.prepare("SELECT * FROM tableName WHERE Id = ?") != .Ok )
{
    /* handle error */
}

statement.bindInt(1, value: 123);

if ( statement.step() == .Row )
{
    /* do something with statement */
    var id:Int = statement.getIntAt(0)
    var stringValue:String? = statement.getStringAt(1)
    var boolValue:Bool = statement.getBoolAt(2)
    var dateValue:NSDate? = statement.getDateAt(3)
}

statement.finalizeStatement(); /* not called finalize() due to destructor/language keyword */

回答4:

I've created an elegant SQLite library written completely in Swift called SwiftData.

Some of its feature are:

Bind objects conveniently to the string of SQL
Support for transactions and savepoints
Inline error handling
Completely thread safe by default

It provides an easy way to execute 'changes' (e.g. INSERT, UPDATE, DELETE, etc.):

if let err = SD.executeChange("INSERT INTO Cities (Name, Population, IsWarm, FoundedIn) VALUES ('Toronto', 2615060, 0, '1793-08-27')") {
    //there was an error during the insert, handle it here
} else {
    //no error, the row was inserted successfully
}

and 'queries' (e.g. SELECT):

let (resultSet, err) = SD.executeQuery("SELECT * FROM Cities")
if err != nil {
    //there was an error during the query, handle it here
} else {
    for row in resultSet {
        if let name = row["Name"].asString() {
            println("The City name is: \(name)")
        }
        if let population = row["Population"].asInt() {
            println("The population is: \(population)")
        }
        if let isWarm = row["IsWarm"].asBool() {
            if isWarm {
                println("The city is warm")
            } else {
                println("The city is cold")
            }
        }
        if let foundedIn = row["FoundedIn"].asDate() {
            println("The city was founded in: \(foundedIn)")
        }
    }
}

Along with many more features!

You can check it out here

回答5:

Yet another SQLite wrapper for Swift 2 and Swift 3: http://github.com/groue/GRDB.swift

Features:

An API that will look familiar to users of ccgus/fmdb
A low-level SQLite API that leverages the Swift standard library
A pretty Swift query interface for SQL-allergic developers
Support for the SQLite WAL mode, and concurrent database access for extra performance
A Record class that wraps result sets, eats your custom SQL queries for breakfast, and provides basic CRUD operations
Swift type freedom: pick the right Swift type that fits your data. Use Int64 when needed, or stick with the convenient Int. Store and read NSDate or NSDateComponents. Declare Swift enums for discrete data types. Define your own database-convertible types.
Database Migrations
Speed: https://github.com/groue/GRDB.swift/wiki/Performance

回答6:

AppDelegate.swift

func createDatabase()
{
    var path:Array=NSSearchPathForDirectoriesInDomains(FileManager.SearchPathDirectory.documentDirectory, FileManager.SearchPathDomainMask.userDomainMask, true)
    let directory:String=path[0]
    let DBpath=(directory as NSString).appendingPathComponent("Food.sqlite")

    print(DBpath)

    if (FileManager.default.fileExists(atPath: DBpath))
    {
        print("Successfull database create")
    }
    else
    {
        let pathfrom:String=(Bundle.main.resourcePath! as NSString).appendingPathComponent("Food.sqlite")

        var success:Bool
        do {
            try FileManager.default.copyItem(atPath: pathfrom, toPath: DBpath)
            success = true
        } catch _ {
            success = false
        }

        if !success
        {
            print("database not create ")
        }
        else
        {
            print("Successfull database new create")
        }
    }
}

Database.swift

import UIKit

class database: NSObject
{
func databasePath() -> NSString
{
    var path:Array=NSSearchPathForDirectoriesInDomains(FileManager.SearchPathDirectory.documentDirectory, FileManager.SearchPathDomainMask.userDomainMask, true)
    let directory:String=path[0] 
    let DBpath=(directory as NSString).appendingPathComponent("Food.sqlite")

    if (FileManager.default.fileExists(atPath: DBpath))
    {
        return DBpath as NSString
    }
    return DBpath as NSString
}

func ExecuteQuery(_ str:String) -> Bool
{
    var result:Bool=false
    let DBpath:String=self.databasePath() as String

    var db: OpaquePointer? = nil
    var stmt:OpaquePointer? = nil

    let strExec=str.cString(using: String.Encoding.utf8)

    if (sqlite3_open(DBpath, &db)==SQLITE_OK)
    {
        if (sqlite3_prepare_v2(db, strExec! , -1, &stmt, nil) == SQLITE_OK)
        {
            if (sqlite3_step(stmt) == SQLITE_DONE)
            {
                result=true
            } 
        }
        sqlite3_finalize(stmt)
    }
    sqlite3_close(db)

    return result
}

func SelectQuery(_ str:String) -> Array<Dictionary<String,String>>
{
    var result:Array<Dictionary<String,String>>=[]
    let DBpath:String=self.databasePath() as String

    var db: OpaquePointer? = nil
    var stmt:OpaquePointer? = nil

    let strExec=str.cString(using: String.Encoding.utf8)

    if ( sqlite3_open(DBpath,&db) == SQLITE_OK)
    {
        if (sqlite3_prepare_v2(db, strExec! , -1, &stmt, nil) == SQLITE_OK)
        {
            while (sqlite3_step(stmt) == SQLITE_ROW)
            {
                var i:Int32=0
                let icount:Int32=sqlite3_column_count(stmt)

                var dict=Dictionary<String, String>()

                while i < icount
                {
                    let strF=sqlite3_column_name(stmt, i)
                    let strV = sqlite3_column_text(stmt, i)

                    let rFiled:String=String(cString: strF!)
                    let rValue:String=String(cString: strV!)
                    //let rValue=String(cString: UnsafePointer<Int8>(strV!))

                    dict[rFiled] = rValue

                    i += 1
                }
                result.insert(dict, at: result.count)
            }
        sqlite3_finalize(stmt)
        }

    sqlite3_close(db)
    }
    return result
}

func AllSelectQuery(_ str:String) -> Array<Model>
{
    var result:Array<Model>=[]
    let DBpath:String=self.databasePath() as String

    var db: OpaquePointer? = nil
    var stmt:OpaquePointer? = nil

    let strExec=str.cString(using: String.Encoding.utf8)

    if ( sqlite3_open(DBpath,&db) == SQLITE_OK)
    {
        if (sqlite3_prepare_v2(db, strExec! , -1, &stmt, nil) == SQLITE_OK)
        {
            while (sqlite3_step(stmt) == SQLITE_ROW)
            {
                let mod=Model()

                mod.id=String(cString: sqlite3_column_text(stmt, 0))
                mod.image=String(cString: sqlite3_column_text(stmt, 1))
                mod.name=String(cString: sqlite3_column_text(stmt, 2))
                mod.foodtype=String(cString: sqlite3_column_text(stmt, 3))
                mod.vegtype=String(cString: sqlite3_column_text(stmt, 4))
                mod.details=String(cString: sqlite3_column_text(stmt, 5))

                result.insert(mod, at: result.count)
            }
            sqlite3_finalize(stmt)
        }
        sqlite3_close(db)
    }
    return result
}

}

Model.swift

import UIKit


class Model: NSObject
{
var uid:Int = 0
var id:String = ""
var image:String = ""
var name:String = ""
var foodtype:String = ""
var vegtype:String = ""
var details:String = ""
var mealtype:String = ""
var date:String = ""
}

Access database :

let DB=database()
var mod=Model()

database Query fire :

var DailyResult:Array<Model> = DB.AllSelectQuery("select * from food where foodtype == 'Sea Food' ORDER BY name ASC")

回答7:

I have written a SQLite3 wrapper library written in Swift.

This is actually a very high level wrapper with very simple API, but anyway, it has low-level C inter-op code, and I post here a (simplified) part of it to shows the C inter-op.

    struct C
    {
        static let  NULL        =   COpaquePointer.null()
    }

    func open(filename:String, flags:OpenFlag)
    {
        let name2   =   filename.cStringUsingEncoding(NSUTF8StringEncoding)!
        let r       =   sqlite3_open_v2(name2, &_rawptr, flags.value, UnsafePointer<Int8>.null())
        checkNoErrorWith(resultCode: r)
    }

    func close()
    {   
        let r   =   sqlite3_close(_rawptr)
        checkNoErrorWith(resultCode: r)
        _rawptr =   C.NULL
    }

    func prepare(SQL:String) -> (statements:[Core.Statement], tail:String)
    {
        func once(zSql:UnsafePointer<Int8>, len:Int32, inout zTail:UnsafePointer<Int8>) -> Core.Statement?
        {
            var pStmt   =   C.NULL
            let r       =   sqlite3_prepare_v2(_rawptr, zSql, len, &pStmt, &zTail)
            checkNoErrorWith(resultCode: r)

            if pStmt == C.NULL
            {
                return  nil
            }
            return  Core.Statement(database: self, pointerToRawCStatementObject: pStmt)
        }

        var stmts:[Core.Statement]  =   []
        let sql2    =   SQL as NSString
        var zSql    =   UnsafePointer<Int8>(sql2.UTF8String)
        var zTail   =   UnsafePointer<Int8>.null()
        var len1    =   sql2.lengthOfBytesUsingEncoding(NSUTF8StringEncoding);
        var maxlen2 =   Int32(len1)+1

        while let one = once(zSql, maxlen2, &zTail)
        {
            stmts.append(one)
            zSql    =   zTail
        }

        let rest1   =   String.fromCString(zTail)
        let rest2   =   rest1 == nil ? "" : rest1!

        return  (stmts, rest2)
    }

    func step() -> Bool
    {   
        let rc1 =   sqlite3_step(_rawptr)

        switch rc1
        {   
            case SQLITE_ROW:
                return  true

            case SQLITE_DONE:
                return  false

            default:
                database.checkNoErrorWith(resultCode: rc1)
        }
    }

    func columnText(at index:Int32) -> String
    {
        let bc  =   sqlite3_column_bytes(_rawptr, Int32(index))
        let cs  =   sqlite3_column_text(_rawptr, Int32(index))

        let s1  =   bc == 0 ? "" : String.fromCString(UnsafePointer<CChar>(cs))!
        return  s1
    }

    func finalize()
    {
        let r   =   sqlite3_finalize(_rawptr)
        database.checkNoErrorWith(resultCode: r)

        _rawptr =   C.NULL
    }

If you want a full source code of this low level wrapper, see these files.

https://github.com/Eonil/SQLite3/blob/master/Swift/Sources/Core.Statement.swift
https://github.com/Eonil/SQLite3/blob/master/Swift/Sources/Core.Database.swift

回答8:

Configure your Swift project to handle SQLite C calls:

Create bridging header file to the project. See the Importing Objective-C into Swift section of the Using Swift with Cocoa and Objective-C. This bridging header should import sqlite3.h:

Add the libsqlite3.0.dylib to your project. See Apple's documentation regarding adding library/framework to one's project.

and used following code

    func executeQuery(query: NSString ) -> Int
    {
        if  sqlite3_open(databasePath! as String, &database) != SQLITE_OK
        {
            println("Databse is not open")
            return 0
        }
        else
        {
            query.stringByReplacingOccurrencesOfString("null", withString: "")
            var cStatement:COpaquePointer = nil
            var executeSql = query as NSString
            var lastId : Int?
            var sqlStatement = executeSql.cStringUsingEncoding(NSUTF8StringEncoding)
            sqlite3_prepare_v2(database, sqlStatement, -1, &cStatement, nil)
            var execute = sqlite3_step(cStatement)
            println("\(execute)")
            if execute == SQLITE_DONE
            {
                lastId = Int(sqlite3_last_insert_rowid(database))
            }
            else
            {
                println("Error in Run Statement :- \(sqlite3_errmsg16(database))")
            }
            sqlite3_finalize(cStatement)
            return lastId!
        }
    }
    func ViewAllData(query: NSString, error: NSError) -> NSArray
    {
        var cStatement = COpaquePointer()
        var result : AnyObject = NSNull()
        var thisArray : NSMutableArray = NSMutableArray(capacity: 4)
        cStatement = prepare(query)
        if cStatement != nil
        {
            while sqlite3_step(cStatement) == SQLITE_ROW
            {
                result = NSNull()
                var thisDict : NSMutableDictionary = NSMutableDictionary(capacity: 4)
                for var i = 0 ; i < Int(sqlite3_column_count(cStatement)) ; i++
                {
                    if sqlite3_column_type(cStatement, Int32(i)) == 0
                    {
                        continue
                    }
                    if sqlite3_column_decltype(cStatement, Int32(i)) != nil && strcasecmp(sqlite3_column_decltype(cStatement, Int32(i)), "Boolean") == 0
                    {
                        var temp = sqlite3_column_int(cStatement, Int32(i))
                        if temp == 0
                        {
                            result = NSNumber(bool : false)
                        }
                        else
                        {
                            result = NSNumber(bool : true)
                        }
                    }
                    else if sqlite3_column_type(cStatement,Int32(i)) == SQLITE_INTEGER
                    {
                        var temp = sqlite3_column_int(cStatement,Int32(i))
                        result = NSNumber(int : temp)
                    }
                    else if sqlite3_column_type(cStatement,Int32(i)) == SQLITE_FLOAT
                    {
                        var temp = sqlite3_column_double(cStatement,Int32(i))
                        result = NSNumber(double: temp)
                    }
                    else
                    {
                        if sqlite3_column_text(cStatement, Int32(i)) != nil
                        {
                            var temp = sqlite3_column_text(cStatement,Int32(i))
                            result = String.fromCString(UnsafePointer<CChar>(temp))!

                            var keyString = sqlite3_column_name(cStatement,Int32(i))
                            thisDict.setObject(result, forKey: String.fromCString(UnsafePointer<CChar>(keyString))!)
                        }
                        result = NSNull()

                    }
                    if result as! NSObject != NSNull()
                    {
                        var keyString = sqlite3_column_name(cStatement,Int32(i))
                        thisDict.setObject(result, forKey: String.fromCString(UnsafePointer<CChar>(keyString))!)
                    }
                }
                thisArray.addObject(NSMutableDictionary(dictionary: thisDict))
            }
            sqlite3_finalize(cStatement)
        }
        return thisArray
    }
    func prepare(sql : NSString) -> COpaquePointer
    {
        var cStatement:COpaquePointer = nil
        sqlite3_open(databasePath! as String, &database)
        var utfSql = sql.UTF8String
        if sqlite3_prepare(database, utfSql, -1, &cStatement, nil) == 0
        {
            sqlite3_close(database)
            return cStatement
        }
        else
        {
            sqlite3_close(database)
            return nil
        }
    }
}

回答9:

Sometimes, a Swift version of the "SQLite in 5 minutes or less" approach shown on sqlite.org is sufficient. The "5 minutes or less" approach uses sqlite3_exec() which is a convenience wrapper for sqlite3_prepare(), sqlite3_step(), sqlite3_column(), and sqlite3_finalize().

Swift 2.2 can directly support the sqlite3_exec() callback function pointer as either a global, non-instance procedure func or a non-capturing literal closure {}.

Readable typealias

typealias sqlite3 = COpaquePointer
typealias CCharHandle = UnsafeMutablePointer<UnsafeMutablePointer<CChar>>
typealias CCharPointer = UnsafeMutablePointer<CChar>
typealias CVoidPointer = UnsafeMutablePointer<Void>

Callback Approach

func callback(
    resultVoidPointer: CVoidPointer, // void *NotUsed 
    columnCount: CInt,               // int argc
    values: CCharHandle,             // char **argv     
    columns: CCharHandle             // char **azColName
    ) -> CInt {
    for  i in 0 ..< Int(columnCount) {
        guard let value = String.fromCString(values[i]) 
        else { continue }
        guard let column = String.fromCString(columns[i]) 
        else { continue }
        print("\(column) = \(value)")
    }
    return 0 // status ok
}

func sqlQueryCallbackBasic(argc: Int, argv: [String]) -> Int {
    var db: sqlite3 = nil 
    var zErrMsg:CCharPointer = nil
    var rc: Int32 = 0 // result code

    if argc != 3 {
        print(String(format: "ERROR: Usage: %s DATABASE SQL-STATEMENT", argv[0]))
        return 1
    }

    rc = sqlite3_open(argv[1], &db)
    if  rc != 0 {
        print("ERROR: sqlite3_open " + String.fromCString(sqlite3_errmsg(db))! ?? "" )
        sqlite3_close(db)
        return 1
    }

    rc = sqlite3_exec(db, argv[2], callback, nil, &zErrMsg)
    if rc != SQLITE_OK {
        print("ERROR: sqlite3_exec " + String.fromCString(zErrMsg)! ?? "")
        sqlite3_free(zErrMsg)
    }

    sqlite3_close(db)
    return 0
}

Closure Approach

func sqlQueryClosureBasic(argc argc: Int, argv: [String]) -> Int {
    var db: sqlite3 = nil 
    var zErrMsg:CCharPointer = nil
    var rc: Int32 = 0

    if argc != 3 {
        print(String(format: "ERROR: Usage: %s DATABASE SQL-STATEMENT", argv[0]))
        return 1
    }

    rc = sqlite3_open(argv[1], &db)
    if  rc != 0 {
        print("ERROR: sqlite3_open " + String.fromCString(sqlite3_errmsg(db))! ?? "" )
        sqlite3_close(db)
        return 1
    }

    rc = sqlite3_exec(
        db,      // database 
        argv[2], // statement
        {        // callback: non-capturing closure
            resultVoidPointer, columnCount, values, columns in

            for i in 0 ..< Int(columnCount) {
                guard let value = String.fromCString(values[i]) 
                else { continue }
                guard let column = String.fromCString(columns[i]) 
                else { continue }
                print("\(column) = \(value)")
            }
            return 0
        }, 
        nil, 
        &zErrMsg
    )

    if rc != SQLITE_OK {
        let errorMsg = String.fromCString(zErrMsg)! ?? ""
        print("ERROR: sqlite3_exec \(errorMsg)")
        sqlite3_free(zErrMsg)
    }
    sqlite3_close(db)
    return 0
}

To prepare an Xcode project to call a C library such as SQLite, one needs to (1) add a Bridging-Header.h file reference C headers like #import "sqlite3.h", (2) add Bridging-Header.h to Objective-C Bridging Header in project settings, and (3) add libsqlite3.tbd to Link Binary With Library target settings.

The sqlite.org's "SQLite in 5 minutes or less" example is implemented in a Swift Xcode7 project here.

回答10:

You can easlity configure SQLite with swift using single ton class as well.

Refer

https://github.com/hasyapanchasara/SQLite_SingleManagerClass

Method to create database

func methodToCreateDatabase() -> NSURL?{}

Method to insert, update and delete data

func methodToInsertUpdateDeleteData(strQuery : String) -> Bool{}

Method to select data

func methodToSelectData(strQuery : String) -> NSMutableArray{}

回答11:

You can use this library in Swift for SQLite https://github.com/pmurphyjam/SQLiteDemo

SQLiteDemo

SQLite Demo using Swift with SQLDataAccess class written in Swift

Adding to Your Project

You only need three files to add to your project * SQLDataAccess.swift * DataConstants.swift * Bridging-Header.h Bridging-Header must be set in your Xcode's project 'Objective-C Bridging Header' under 'Swift Compiler - General'

Examples for Use

Just follow the code in ViewController.swift to see how to write simple SQL with SQLDataAccess.swift First you need to open the SQLite Database your dealing with

```swift
let db = SQLDataAccess.shared
db.setDBName(name:"SQLite.db")
let opened = db.openConnection(copyFile:true)
```

If openConnection succeeded, now you can do a simple insert into Table AppInfo

```swift
//Insert into Table AppInfo
let status = db.executeStatement("insert into AppInfo (name,value,descrip,date) values(?,?,?,?)",
”SQLiteDemo","1.0.2","unencrypted",Date())
if(status)
{
    //Read Table AppInfo into an Array of Dictionaries
    let results = db.getRecordsForQuery("select * from AppInfo ")
    NSLog("Results = \(results)")
}
```

See how simple that was!

The first term in db.executeStatement is your SQL as String, all the terms that follow are a variadic argument list of type Any, and are your parameters in an Array. All these terms are separated by commas in your list of SQL arguments. You can enter Strings, Integers, Date’s, and Blobs right after the sequel statement since all of these terms are considered to be parameters for the sequel. The variadic argument array just makes it convenient to enter all your sequel in just one executeStatement or getRecordsForQuery call. If you don’t have any parameters, don’t enter anything after your SQL.

The results array is an Array of Dictionary’s where the ‘key’ is your tables column name, and the ‘value’ is your data obtained from SQLite. You can easily iterate through this array with a for loop or print it out directly or assign these Dictionary elements to custom data object Classes that you use in your View Controllers for model consumption.

```swift
for dic in results as! [[String:AnyObject]] {
   print(“result = \(dic)”)
}


```

SQLDataAccess will store, text, double, float, blob, Date, integer and long long integers. For Blobs you can store binary, varbinary, blob.

For Text you can store char, character, clob, national varying character, native character, nchar, nvarchar, varchar, variant, varying character, text.

For Dates you can store datetime, time, timestamp, date.

For Integers you can store bigint, bit, bool, boolean, int2, int8, integer, mediumint, smallint, tinyint, int.

For Doubles you can store decimal, double precision, float, numeric, real, double. Double has the most precision.

You can even store Nulls of type Null.

In ViewController.swift a more complex example is done showing how to insert a Dictionary as a 'Blob'. In addition SQLDataAccess understands native Swift Date() so you can insert these objects with out converting, and it will convert them to text and store them, and when retrieved convert them back from text to Date.

Of course the real power of SQLite is it's Transaction capability. Here you can literally queue up 400 SQL statements with parameters and insert them all at once which is really powerful since it's so fast. ViewController.swift also shows you an example of how to do this. All you're really doing is creating an Array of Dictionaries called 'sqlAndParams', in this Array your storing Dictionaries with two keys 'SQL' for the String sequel statement or query, and 'PARAMS' which is just an Array of native objects SQLite understands for that query. Each 'sqlParams' which is an individual Dictionary of sequel query plus parameters is then stored in the 'sqlAndParams' Array. Once you've created this array, you just call.

```swift
let status = db.executeTransaction(sqlAndParams)
if(status)
{
    //Read Table AppInfo into an Array of Dictionaries for the above Transactions
    let results = db.getRecordsForQuery("select * from AppInfo ")
    NSLog("Results = \(results)")
}
```

In addition all executeStatement and getRecordsForQuery methods can be done with simple String for SQL query and an Array for the parameters needed by the query.

```swift
let sql : String = "insert into AppInfo (name,value,descrip) values(?,?,?)"
let params : Array = ["SQLiteDemo","1.0.0","unencrypted"]
let status = db.executeStatement(sql, withParameters: params)
if(status)
{
    //Read Table AppInfo into an Array of Dictionaries for the above Transactions
    let results = db.getRecordsForQuery("select * from AppInfo ")
    NSLog("Results = \(results)")
}
```

An Objective-C version also exists and is called the same SQLDataAccess, so now you can choose to write your sequel in Objective-C or Swift. In addition SQLDataAccess will also work with SQLCipher, the present code isn't setup yet to work with it, but it's pretty easy to do, and an example of how to do this is actually in the Objective-C version of SQLDataAccess.

SQLDataAccess is a very fast and efficient class, and can be used in place of CoreData which really just uses SQLite as it's underlying data store without all the CoreData core data integrity fault crashes that come with CoreData.

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