Using Sqlite3 in Swift

Import Foundation/**1. Open the Database2. If there is no data table, you need to first create a table3. Data operation */Class SQLite {var db:copaquepointer = Nil ///Open Database /// ///:p Aram:dbname Database name /// ///: Returns: whether to open successfullyFunc OpenDatabase (dbname:string), Bool {  //Unsafepointer<int8> unsafepointer<cchar>  //corresponding to char* in C language  //FileName must be the full path name Let path = Dbname.documentpath () println (PATH)  //Sqlite3_open If the database does not exist, a new database file is created  //If the database file already exists, open it directly and return the handle without any effect on the data  If Sqlite3_open (path, &db) = = SQLITE_OK {  println"Open Database Succeeded ")   //Essentially, it only needs to be run once.   If CreateTable () {   println"Success of the Record ")    //TODO: Test Query data   Let sql ="Select ID, Departmentno, Name from T_department; "   RecordSet (SQL)  }else {   println"Failed to create a table ")  } }else {  println"Failed to open database ") }  ReturnFalse} ///Create a data table, create a data table that the system needs, once Private Func createtable (), Bool {  //Prepare SQL for all data tables  //1> each SQL is completed with one;  //2> Write all the Genesis SQL together, adding a \ n for each line break Let sql ="CREATE TABLE \ n "+   "IF not EXISTS t_department (\ n "+   "ID INTEGER PRIMARY KEY autoincrement not null,\n "+   "Departmentno CHAR (Ten) not NULL DEFAULT ' ', \ n ' +   "Name CHAR (a) not NULL DEFAULT ' \ n ' +   "); \ n "+   "CREATE TABLE IF not EXISTS t_employee (\ n "+   "' ID ' INTEGER not NULL PRIMARY KEY autoincrement, \ n ' +   "' Name ' TEXT not NULL, \ n ' +   "' Age ' INTEGER is not NULL, \ n ' +   "' department_id ' INTEGER, \ n ' +   "CONSTRAINT ' fk_dep_id ' FOREIGN KEY (' department_id ') REFERENCES ' t_department ' (' ID ') \ n "+  ");"  return Execsql (SQL)} ///Execute SQL statement with no return value /// ///:p Aram:sql SQL string /// ///: Returns: whether successfulFunc Execsql (sql:string), Bool {  /**  1. Database pointers  2. C language format for SQL strings  3. Callback, function callback after the completion of the SQL command, usually nil  4. A pointer to the first parameter of the callback  5. Error messages, usually also passing nil */  Return sqlite3_exec (DB, sql.cstringusingencoding (nsutf8stringencoding)!, nil, nil, nil) = = Sqlite_ok} ///Execute SQL Returns a result set (object array) /// ///:p Aram:sql SQL stringFunc RecordSet (sql:string) {  //1. Prepare the statement var stmt:copaquepointer = Nil  /**  1. Database handle  2. SQL's C-language string  3. The string length of the C language of SQL strlen,-1 is automatically calculated  4. Pointers to stmt  5. Usually pass in nil */  If SQLITE3_PREPARE_V2 (db, Sql.cstringusingencoding (nsutf8stringencoding)!,-1, &stmt, nil) = = SQLITE_OK {   //Single-Step Get SQL Execution results-Sqlite3_setup corresponds to a record   While Sqlite3_step (stmt) = = Sqlite_row {    //Get the data for each record   RecordData (stmt)  } }} ///Get a record of each piece of data /// ///:p aram:stmt prepared_statement ObjectsFunc RecordData (stmt:copaquepointer) {  //Get to record var count = Sqlite3_column_count (stmt) println"Get to record, total number of columns \ (count) ")  //Traverse data for each column  For I in0.. <count {  Let type = Sqlite3_column_type (stmt, i)   //Extracts the value of the corresponding column based on the type of the field   Switch type {   Case Sqlite_integer:   println"Integer \ (Sqlite3_column_int64 (stmt, i))   Case Sqlite_float:   println"Small tree \ (sqlite3_column_double (stmt, i))   Case Sqlite_null:   println"Empty \ (NSNull ()) ")   Case Sqlite_text:    let chars = Unsafepointer<cchar> (Sqlite3_column_text (stmt, i))  Span class= "indent" >   let str = String (cstring:chars, encoding: nsutf8stringencoding)!     println ( " string \ (str)")    case let type:    println ( "  Span class= "indent" >} }}}     

Using Sqlite3 in Swift