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//
// Copyright (c) 2009-2010 Krueger Systems, Inc.
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
//
using System;
using System.Runtime.InteropServices;
using System.Collections.Generic;
using System.Reflection;
using System.Linq;
using System.Linq.Expressions;
namespace SQLite
{
public class SQLiteException : System.Exception
{
public SQLite3.Result Result { get; private set; }
protected SQLiteException (SQLite3.Result r, string message) : base(message)
{
Result = r;
}
public static SQLiteException New (SQLite3.Result r, string message)
{
return new SQLiteException (r, message);
}
}
/// <summary>
/// Represents an open connection to a SQLite database.
/// </summary>
public class SQLiteConnection : IDisposable
{
private bool _open;
private TimeSpan _busyTimeout;
private Dictionary<string, TableMapping> _mappings = null;
private Dictionary<string, TableMapping> _tables = null;
private System.Diagnostics.Stopwatch _sw;
private long _elapsedMilliseconds = 0;
public IntPtr Handle { get; private set; }
public string DatabasePath { get; private set; }
public bool TimeExecution { get; set; }
public bool Trace { get; set; }
/// <summary>
/// Constructs a new SQLiteConnection and opens a SQLite database specified by databasePath.
/// </summary>
/// <param name="databasePath">
/// Specifies the path to the database file.
/// </param>
public SQLiteConnection (string databasePath)
{
DatabasePath = databasePath;
IntPtr handle;
var r = SQLite3.Open (DatabasePath, out handle);
Handle = handle;
if (r != SQLite3.Result.OK) {
throw SQLiteException.New (r, "Could not open database file: " + DatabasePath);
}
_open = true;
BusyTimeout = TimeSpan.FromSeconds (0.1);
}
/// <summary>
/// Sets a busy handler to sleep the specified amount of time when a table is locked.
/// The handler will sleep multiple times until a total time of <see cref="BusyTimeout"/> has accumulated.
/// </summary>
public TimeSpan BusyTimeout {
get { return _busyTimeout; }
set {
_busyTimeout = value;
if (Handle != IntPtr.Zero) {
SQLite3.BusyTimeout (Handle, (int)_busyTimeout.TotalMilliseconds);
}
}
}
/// <summary>
/// Returns the mappings from types to tables that the connection
/// currently understands.
/// </summary>
public IEnumerable<TableMapping> TableMappings {
get {
if (_tables == null) {
return Enumerable.Empty<TableMapping> ();
} else {
return _tables.Values;
}
}
}
/// <summary>
/// Retrieves the mapping that is automatically generated for the given type.
/// </summary>
/// <param name="type">
/// The type whose mapping to the database is returned.
/// </param>
/// <returns>
/// The mapping represents the schema of the columns of the database and contains
/// methods to set and get properties of objects.
/// </returns>
public TableMapping GetMapping (Type type)
{
if (_mappings == null) {
_mappings = new Dictionary<string, TableMapping> ();
}
TableMapping map;
if (!_mappings.TryGetValue (type.FullName, out map)) {
map = new TableMapping (type);
_mappings[type.FullName] = map;
}
return map;
}
/// <summary>
/// Executes a "create table if not exists" on the database. It also
/// creates any specified indexes on the columns of the table. It uses
/// a schema automatically generated from the specified type. You can
/// later access this schema by calling GetMapping.
/// </summary>
/// <returns>
/// The number of entries added to the database schema.
/// </returns>
public int CreateTable<T> ()
{
var ty = typeof(T);
if (_tables == null) {
_tables = new Dictionary<string, TableMapping> ();
}
TableMapping map;
if (!_tables.TryGetValue (ty.FullName, out map)) {
map = GetMapping (ty);
_tables.Add (ty.FullName, map);
}
var query = "create table if not exists \"" + map.TableName + "\"(\n";
var decls = map.Columns.Select (p => Orm.SqlDecl (p));
var decl = string.Join (",\n", decls.ToArray ());
query += decl;
query += ")";
var count = Execute (query);
foreach (var p in map.Columns.Where (x => x.IsIndexed)) {
var indexName = map.TableName + "_" + p.Name;
var q = string.Format ("create index if not exists \"{0}\" on \"{1}\"(\"{2}\")", indexName, map.TableName, p.Name);
count += Execute (q);
}
return count;
}
/// <summary>
/// Creates a new SQLiteCommand given the command text with arguments. Place a '?'
/// in the command text for each of the arguments.
/// </summary>
/// <param name="cmdText">
/// The fully escaped SQL.
/// </param>
/// <param name="args">
/// Arguments to substitute for the occurences of '?' in the command text.
/// </param>
/// <returns>
/// A <see cref="SQLiteCommand"/>
/// </returns>
public SQLiteCommand CreateCommand (string cmdText, params object[] ps)
{
if (!_open) {
throw SQLiteException.New (SQLite3.Result.Error, "Cannot create commands from unopened database");
} else {
var cmd = new SQLiteCommand (this);
cmd.CommandText = cmdText;
foreach (var o in ps) {
cmd.Bind (o);
}
return cmd;
}
}
/// <summary>
/// Creates a SQLiteCommand given the command text (SQL) with arguments. Place a '?'
/// in the command text for each of the arguments and then executes that command.
/// Use this method instead of Query when you don't expect rows back. Such cases include
/// INSERTs, UPDATEs, and DELETEs.
/// You can set the Trace or TimeExecution properties of the connection
/// to profile execution.
/// </summary>
/// <param name="query">
/// The fully escaped SQL.
/// </param>
/// <param name="args">
/// Arguments to substitute for the occurences of '?' in the query.
/// </param>
/// <returns>
/// The number of rows modified in the database as a result of this execution.
/// </returns>
public int Execute (string query, params object[] args)
{
var cmd = CreateCommand (query, args);
if (TimeExecution) {
if (_sw == null) {
_sw = new System.Diagnostics.Stopwatch ();
}
_sw.Reset ();
_sw.Start ();
}
int r = cmd.ExecuteNonQuery ();
if (TimeExecution) {
_sw.Stop ();
_elapsedMilliseconds += _sw.ElapsedMilliseconds;
Console.WriteLine ("Finished in {0} ms ({1:0.0} s total)", _sw.ElapsedMilliseconds, _elapsedMilliseconds / 1000.0);
}
return r;
}
/// <summary>
/// Creates a SQLiteCommand given the command text (SQL) with arguments. Place a '?'
/// in the command text for each of the arguments and then executes that command.
/// It returns each row of the result using the mapping automatically generated for
/// the given type.
/// </summary>
/// <param name="query">
/// The fully escaped SQL.
/// </param>
/// <param name="args">
/// Arguments to substitute for the occurences of '?' in the query.
/// </param>
/// <returns>
/// An enumerable with one result for each row returned by the query.
/// </returns>
public List<T> Query<T> (string query, params object[] args) where T : new()
{
var cmd = CreateCommand (query, args);
return cmd.ExecuteQuery<T> ();
}
/// <summary>
/// Creates a SQLiteCommand given the command text (SQL) with arguments. Place a '?'
/// in the command text for each of the arguments and then executes that command.
/// It returns each row of the result using the specified mapping. This function is
/// only used by libraries in order to query the database via introspection. It is
/// normally not used.
/// </summary>
/// <param name="map">
/// A <see cref="TableMapping"/> to use to convert the resulting rows
/// into objects.
/// </param>
/// <param name="query">
/// The fully escaped SQL.
/// </param>
/// <param name="args">
/// Arguments to substitute for the occurences of '?' in the query.
/// </param>
/// <returns>
/// An enumerable with one result for each row returned by the query.
/// </returns>
public List<object> Query (TableMapping map, string query, params object[] args)
{
var cmd = CreateCommand (query, args);
return cmd.ExecuteQuery<object> (map);
}
/// <summary>
/// Returns a queryable interface to the table represented by the given type.
/// </summary>
/// <returns>
/// A queryable object that is able to translate Where, OrderBy, and Take
/// queries into native SQL.
/// </returns>
public TableQuery<T> Table<T> () where T : new()
{
return new TableQuery<T> (this);
}
/// <summary>
/// Attempts to retrieve an object with the given primary key from the table
/// associated with the specified type. Use of this method requires that
/// the given type have a designated PrimaryKey (using the PrimaryKeyAttribute).
/// </summary>
/// <param name="pk">
/// The primary key.
/// </param>
/// <returns>
/// The object with the given primary key. Throws a not found exception
/// if the object is not found.
/// </returns>
public T Get<T> (object pk) where T : new()
{
var map = GetMapping (typeof(T));
string query = string.Format ("select * from \"{0}\" where \"{1}\" = ?", map.TableName, map.PK.Name);
return Query<T> (query, pk).First ();
}
/// <summary>
/// Whether <see cref="BeginTransaction"/> has been called and the database is waiting for a <see cref="Commit"/>.
/// </summary>
public bool IsInTransaction { get; private set; }
/// <summary>
/// Begins a new transaction. Call <see cref="Commit"/> to end the transaction.
/// </summary>
public void BeginTransaction ()
{
if (!IsInTransaction) {
Execute ("begin transaction");
IsInTransaction = true;
}
}
/// <summary>
/// Rolls back the transaction that was begun by <see cref="BeginTransaction"/>.
/// </summary>
public void Rollback ()
{
if (IsInTransaction) {
Execute ("rollback");
IsInTransaction = false;
}
}
/// <summary>
/// Commits the transaction that was begun by <see cref="BeginTransaction"/>.
/// </summary>
public void Commit ()
{
if (IsInTransaction) {
Execute ("commit");
IsInTransaction = false;
}
}
/// <summary>
/// Executes <param name="action"> within a transaction and automatically rollsback the transaction
/// if an exception occurs. The exception is rethrown.
/// </summary>
/// <param name="action">
/// The <see cref="Action"/> to perform within a transaction. <param name="action"> can contain any number
/// of operations on the connection but should never call <see cref="BeginTransaction"/>,
/// <see cref="Rollback"/>, or <see cref="Commit"/>.
/// </param>
public void RunInTransaction (Action action)
{
if (IsInTransaction) {
throw new InvalidOperationException ("The connection must not already be in a transaction when RunInTransaction is called");
}
try {
BeginTransaction ();
action ();
Commit ();
} catch (Exception) {
Rollback ();
throw;
}
}
/// <summary>
/// Inserts all specified objects.
/// </summary>
/// <param name="objects">
/// An <see cref="IEnumerable"/> of the objects to insert.
/// </param>
/// <returns>
/// The number of rows added to the table.
/// </returns>
public int InsertAll (System.Collections.IEnumerable objects)
{
BeginTransaction ();
var c = 0;
foreach (var r in objects) {
c += Insert (r);
}
Commit ();
return c;
}
/// <summary>
/// Inserts the given object and retrieves its
/// auto incremented primary key if it has one.
/// </summary>
/// <param name="obj">
/// The object to insert.
/// </param>
/// <returns>
/// The number of rows added to the table.
/// </returns>
public int Insert (object obj)
{
if (obj == null) {
return 0;
}
return Insert (obj, "", obj.GetType ());
}
public int Insert (object obj, Type objType)
{
return Insert (obj, "", objType);
}
public int Insert (object obj, string extra)
{
if (obj == null) {
return 0;
}
return Insert (obj, extra, obj.GetType ());
}
/// <summary>
/// Inserts the given object and retrieves its
/// auto incremented primary key if it has one.
/// </summary>
/// <param name="obj">
/// The object to insert.
/// </param>
/// <param name="extra">
/// Literal SQL code that gets placed into the command. INSERT {extra} INTO ...
/// </param>
/// <returns>
/// The number of rows added to the table.
/// </returns>
public int Insert (object obj, string extra, Type objType)
{
if (obj == null || objType == null) {
return 0;
}
var map = GetMapping (objType);
var cols = map.InsertColumns;
var vals = new object[cols.Length];
for (var i = 0; i < vals.Length; i++) {
vals[i] = cols[i].GetValue (obj);
}
var count = Execute (map.InsertSql (extra), vals);
var id = SQLite3.LastInsertRowid (Handle);
map.SetAutoIncPK (obj, id);
return count;
}
/// <summary>
/// Updates all of the columns of a table using the specified object
/// except for its primary key.
/// The object is required to have a primary key.
/// </summary>
/// <param name="obj">
/// The object to update. It must have a primary key designated using the PrimaryKeyAttribute.
/// </param>
/// <returns>
/// The number of rows updated.
/// </returns>
public int Update (object obj)
{
if (obj == null) {
return 0;
}
return Update (obj, obj.GetType ());
}
public int Update (object obj, Type objType)
{
if (obj == null || objType == null) {
return 0;
}
var map = GetMapping (objType);
var pk = map.PK;
if (pk == null) {
throw new NotSupportedException ("Cannot update " + map.TableName + ": it has no PK");
}
var cols = from p in map.Columns
where p != pk
select p;
var vals = from c in cols
select c.GetValue (obj);
var ps = new List<object> (vals);
ps.Add (pk.GetValue (obj));
var q = string.Format ("update \"{0}\" set {1} where {2} = ? ", map.TableName, string.Join (",", (from c in cols
select "\"" + c.Name + "\" = ? ").ToArray ()), pk.Name);
return Execute (q, ps.ToArray ());
}
/// <summary>
/// Deletes the given object from the database using its primary key.
/// </summary>
/// <param name="obj">
/// The object to delete. It must have a primary key designated using the PrimaryKeyAttribute.
/// </param>
/// <returns>
/// The number of rows deleted.
/// </returns>
public int Delete<T> (T obj)
{
var map = GetMapping (obj.GetType ());
var pk = map.PK;
if (pk == null) {
throw new NotSupportedException ("Cannot delete " + map.TableName + ": it has no PK");
}
var q = string.Format ("delete from \"{0}\" where \"{1}\" = ?", map.TableName, pk.Name);
return Execute (q, pk.GetValue (obj));
}
public void Dispose ()
{
Close ();
}
public void Close ()
{
if (_open && Handle != IntPtr.Zero) {
SQLite3.Close (Handle);
Handle = IntPtr.Zero;
_open = false;
}
}
}
public class PrimaryKeyAttribute : Attribute
{
}
public class AutoIncrementAttribute : Attribute
{
}
public class IndexedAttribute : Attribute
{
}
public class IgnoreAttribute : Attribute
{
}
public class MaxLengthAttribute : Attribute
{
public int Value { get; private set; }
public MaxLengthAttribute (int length)
{
Value = length;
}
}
public class TableMapping
{
public Type MappedType { get; private set; }
public string TableName { get; private set; }
public Column[] Columns { get; private set; }
public Column PK { get; private set; }
Column _autoPk = null;
Column[] _insertColumns = null;
string _insertSql = null;
public TableMapping (Type type)
{
MappedType = type;
TableName = MappedType.Name;
var props = MappedType.GetProperties (BindingFlags.Public | BindingFlags.Instance | BindingFlags.SetProperty);
var cols = new List<Column> ();
foreach (var p in props) {
var ignore = p.GetCustomAttributes (typeof(IgnoreAttribute), true).Length > 0;
if (p.CanWrite && !ignore) {
cols.Add (new PropColumn (p));
}
}
Columns = cols.ToArray ();
foreach (var c in Columns) {
if (c.IsAutoInc && c.IsPK) {
_autoPk = c;
}
if (c.IsPK) {
PK = c;
}
}
}
public void SetAutoIncPK (object obj, long id)
{
if (_autoPk != null) {
_autoPk.SetValue (obj, Convert.ChangeType (id, _autoPk.ColumnType));
}
}
public Column[] InsertColumns {
get {
if (_insertColumns == null) {
_insertColumns = Columns.Where (c => !c.IsAutoInc).ToArray ();
}
return _insertColumns;
}
}
public Column FindColumn (string name)
{
var exact = Columns.Where (c => c.Name == name).FirstOrDefault ();
return exact;
}
public string InsertSql (string extra)
{
if (_insertSql == null) {
var cols = InsertColumns;
_insertSql = string.Format ("insert {3} into \"{0}\"({1}) values ({2})", TableName, string.Join (",", (from c in cols
select "\"" + c.Name + "\"").ToArray ()), string.Join (",", (from c in cols
select "?").ToArray ()), extra);
}
return _insertSql;
}
public abstract class Column
{
public string Name { get; protected set; }
public Type ColumnType { get; protected set; }
public bool IsAutoInc { get; protected set; }
public bool IsPK { get; protected set; }
public bool IsIndexed { get; protected set; }
public bool IsNullable { get; protected set; }
public int MaxStringLength { get; protected set; }
public abstract void SetValue (object obj, object val);
public abstract object GetValue (object obj);
}
public class PropColumn : Column
{
PropertyInfo _prop;
public PropColumn (PropertyInfo prop)
{
_prop = prop;
Name = prop.Name;
ColumnType = prop.PropertyType;
IsAutoInc = Orm.IsAutoInc (prop);
IsPK = Orm.IsPK (prop);
IsIndexed = Orm.IsIndexed (prop);
IsNullable = !IsPK;
MaxStringLength = Orm.MaxStringLength (prop);
}
public override void SetValue (object obj, object val)
{
_prop.SetValue (obj, val, null);
}
public override object GetValue (object obj)
{
return _prop.GetValue (obj, null);
}
}
}
public static class Orm
{
public const int DefaultMaxStringLength = 140;
public static string SqlDecl (TableMapping.Column p)
{
string decl = "\"" + p.Name + "\" " + SqlType (p) + " ";
if (p.IsPK) {
decl += "primary key ";
}
if (p.IsAutoInc) {
decl += "autoincrement ";
}
if (!p.IsNullable) {
decl += "not null ";
}
return decl;
}
public static string SqlType (TableMapping.Column p)
{
var clrType = p.ColumnType;
if (clrType == typeof(Boolean) || clrType == typeof(Byte) || clrType == typeof(UInt16) || clrType == typeof(SByte) || clrType == typeof(Int16) || clrType == typeof(Int32)) {
return "integer";
} else if (clrType == typeof(UInt32) || clrType == typeof(Int64)) {
return "bigint";
} else if (clrType == typeof(Single) || clrType == typeof(Double) || clrType == typeof(Decimal)) {
return "float";
} else if (clrType == typeof(String)) {
int len = p.MaxStringLength;
return "varchar(" + len + ")";
} else if (clrType == typeof(DateTime)) {
return "datetime";
} else if (clrType.IsEnum) {
return "integer";
} else {
throw new NotSupportedException ("Don't know about " + clrType);
}
}
public static bool IsPK (MemberInfo p)
{
var attrs = p.GetCustomAttributes (typeof(PrimaryKeyAttribute), true);
return attrs.Length > 0;
}
public static bool IsAutoInc (MemberInfo p)
{
var attrs = p.GetCustomAttributes (typeof(AutoIncrementAttribute), true);
return attrs.Length > 0;
}
public static bool IsIndexed (MemberInfo p)
{
var attrs = p.GetCustomAttributes (typeof(IndexedAttribute), true);
return attrs.Length > 0;
}
public static int MaxStringLength (PropertyInfo p)
{
var attrs = p.GetCustomAttributes (typeof(MaxLengthAttribute), true);
if (attrs.Length > 0) {
return ((MaxLengthAttribute)attrs[0]).Value;
} else {
return DefaultMaxStringLength;
}
}
}
public class SQLiteCommand
{
SQLiteConnection _conn;
private List<Binding> _bindings;
public string CommandText { get; set; }
internal SQLiteCommand (SQLiteConnection conn)
{
_conn = conn;
_bindings = new List<Binding> ();
CommandText = "";
}
public int ExecuteNonQuery ()
{
if (_conn.Trace) {
Console.WriteLine ("Executing: " + this);
}
var r = SQLite3.Result.OK;
var stmt = Prepare ();
r = SQLite3.Step (stmt);
Finalize (stmt);
if (r == SQLite3.Result.Done) {
int rowsAffected = SQLite3.Changes (_conn.Handle);
return rowsAffected;
} else if (r == SQLite3.Result.Error) {
string msg = SQLite3.GetErrmsg (_conn.Handle);
throw SQLiteException.New (r, msg);
} else {
throw SQLiteException.New (r, r.ToString ());
}
}
public List<T> ExecuteQuery<T> () where T : new()
{
return ExecuteQuery<T> (_conn.GetMapping (typeof(T)));
}
class ColRef
{
public SQLite3.ColType ColType;
public TableMapping.Column MappingColumn;
}
public List<T> ExecuteQuery<T> (TableMapping map)
{
if (_conn.Trace) {
Console.WriteLine ("Executing Query: " + this);
}
var r = new List<T> ();
var stmt = Prepare ();
var cols = new ColRef[SQLite3.ColumnCount (stmt)];
for (int i = 0; i < cols.Length; i++) {
var name = Marshal.PtrToStringUni (SQLite3.ColumnName16 (stmt, i));
cols[i] = new ColRef ();
cols[i].MappingColumn = map.FindColumn (name);
}
var first = true;
while (SQLite3.Step (stmt) == SQLite3.Result.Row) {
var obj = Activator.CreateInstance (map.MappedType);
for (int i = 0; i < cols.Length; i++) {
if (cols[i].MappingColumn == null)
continue;
if (first) {
cols[i].ColType = SQLite3.ColumnType (stmt, i);
}
var val = ReadCol (stmt, i, cols[i].ColType, cols[i].MappingColumn.ColumnType);
cols[i].MappingColumn.SetValue (obj, val);
}
first = false;
r.Add ((T)obj);
}
Finalize (stmt);
return r;
}
public T ExecuteScalar<T> ()
{
T val = default(T);
var stmt = Prepare ();
if (SQLite3.Step (stmt) == SQLite3.Result.Row) {
var colType = SQLite3.ColumnType (stmt, 0);
val = (T)ReadCol (stmt, 0, colType, typeof(T));
}
Finalize (stmt);
return val;
}
public void Bind (string name, object val)
{
_bindings.Add (new Binding {
Name = name,
Value = val
});
}
public void Bind (object val)
{
Bind (null, val);
}
public override string ToString ()
{
var parts = new string[1 + _bindings.Count];
parts[0] = CommandText;
var i = 1;
foreach (var b in _bindings) {
parts[i] = string.Format (" {0}: {1}", i - 1, b.Value);
i++;
}
return string.Join (Environment.NewLine, parts);
}
IntPtr Prepare ()
{
var stmt = SQLite3.Prepare2 (_conn.Handle, CommandText);
BindAll (stmt);
return stmt;
}
void Finalize (IntPtr stmt)
{
SQLite3.Finalize (stmt);
}
void BindAll (IntPtr stmt)
{
int nextIdx = 1;
foreach (var b in _bindings) {
if (b.Name != null) {
b.Index = SQLite3.BindParameterIndex (stmt, b.Name);
} else {
b.Index = nextIdx++;
}
}
foreach (var b in _bindings) {
if (b.Value == null) {
SQLite3.BindNull (stmt, b.Index);
} else {
var bty = b.Value.GetType ();
if (b.Value is Int32) {
SQLite3.BindInt (stmt, b.Index, (int)b.Value);
} else if (b.Value is String) {
SQLite3.BindText (stmt, b.Index, (string)b.Value, -1, new IntPtr (-1));
} else if (b.Value is Byte || b.Value is UInt16 || b.Value is SByte || b.Value is Int16) {
SQLite3.BindInt (stmt, b.Index, Convert.ToInt32 (b.Value));
} else if (b.Value is Boolean) {
SQLite3.BindInt (stmt, b.Index, (bool)b.Value ? 1 : 0);
} else if (b.Value is UInt32 || b.Value is Int64) {
SQLite3.BindInt64 (stmt, b.Index, Convert.ToInt64 (b.Value));
} else if (b.Value is Single || b.Value is Double || b.Value is Decimal) {
SQLite3.BindDouble (stmt, b.Index, Convert.ToDouble (b.Value));
} else if (b.Value is DateTime) {
SQLite3.BindText (stmt, b.Index, ((DateTime)b.Value).ToString ("yyyy-MM-dd HH:mm:ss"), -1, new IntPtr (-1));
} else if (bty.IsEnum) {
SQLite3.BindInt (stmt, b.Index, Convert.ToInt32 (b.Value));
}
}
}
}
class Binding
{
public string Name { get; set; }
public object Value { get; set; }
public int Index { get; set; }
}
object ReadCol (IntPtr stmt, int index, SQLite3.ColType type, Type clrType)
{
if (type == SQLite3.ColType.Null) {
return null;
} else {
if (clrType == typeof(String)) {
return SQLite3.ColumnString (stmt, index);
} else if (clrType == typeof(Int32)) {
return (int)SQLite3.ColumnInt (stmt, index);
} else if (clrType == typeof(Boolean)) {
return SQLite3.ColumnInt (stmt, index) == 1;
} else if (clrType == typeof(double)) {
return SQLite3.ColumnDouble (stmt, index);
} else if (clrType == typeof(float)) {
return (float)SQLite3.ColumnDouble (stmt, index);
} else if (clrType == typeof(DateTime)) {
var text = SQLite3.ColumnString (stmt, index);
return DateTime.Parse (text);
} else if (clrType.IsEnum) {
return SQLite3.ColumnInt (stmt, index);
} else if (clrType == typeof(Int64)) {
return SQLite3.ColumnInt64 (stmt, index);
} else if (clrType == typeof(UInt32)) {
return (uint)SQLite3.ColumnInt64 (stmt, index);
} else if (clrType == typeof(decimal)) {
return (decimal)SQLite3.ColumnDouble (stmt, index);
} else if (clrType == typeof(Byte)) {
return (byte)SQLite3.ColumnInt (stmt, index);
} else if (clrType == typeof(UInt16)) {
return (ushort)SQLite3.ColumnInt (stmt, index);
} else if (clrType == typeof(Int16)) {
return (short)SQLite3.ColumnInt (stmt, index);
} else if (clrType == typeof(sbyte)) {
return (sbyte)SQLite3.ColumnInt (stmt, index);
} else {
throw new NotSupportedException ("Don't know how to read " + clrType);
}
}
}
}
public class TableQuery<T> : IEnumerable<T> where T : new()
{
public SQLiteConnection Connection { get; private set; }
public TableMapping Table { get; private set; }
Expression _where;
List<Ordering> _orderBys;
int? _limit;
int? _offset;
class Ordering
{
public string ColumnName { get; set; }
public bool Ascending { get; set; }
}
TableQuery (SQLiteConnection conn, TableMapping table)
{
Connection = conn;
Table = table;
}
public TableQuery (SQLiteConnection conn)
{
Connection = conn;
Table = Connection.GetMapping (typeof(T));
}
public TableQuery<T> Clone ()
{
var q = new TableQuery<T> (Connection, Table);
q._where = _where;
if (_orderBys != null) {
q._orderBys = new List<Ordering> (_orderBys);
}
q._limit = _limit;
q._offset = _offset;
return q;
}
public TableQuery<T> Where (Expression<Func<T, bool>> predExpr)
{
if (predExpr.NodeType == ExpressionType.Lambda) {
var lambda = (LambdaExpression)predExpr;
var pred = lambda.Body;
var q = Clone ();
q.AddWhere (pred);
return q;
} else {
throw new NotSupportedException ("Must be a predicate");
}
}
public TableQuery<T> Take (int n)
{
var q = Clone ();
q._limit = n;
return q;
}
public TableQuery<T> Skip (int n)
{
var q = Clone ();
q._offset = n;
return q;
}
public TableQuery<T> OrderBy<U> (Expression<Func<T, U>> orderExpr)
{
return AddOrderBy<U> (orderExpr, true);
}
public TableQuery<T> OrderByDescending<U> (Expression<Func<T, U>> orderExpr)
{
return AddOrderBy<U> (orderExpr, false);
}
private TableQuery<T> AddOrderBy<U> (Expression<Func<T, U>> orderExpr, bool asc)
{
if (orderExpr.NodeType == ExpressionType.Lambda) {
var lambda = (LambdaExpression)orderExpr;
var mem = lambda.Body as MemberExpression;
if (mem != null && (mem.Expression.NodeType == ExpressionType.Parameter)) {
var q = Clone ();
if (q._orderBys == null) {
q._orderBys = new List<Ordering> ();
}
q._orderBys.Add (new Ordering {
ColumnName = mem.Member.Name,
Ascending = asc
});
return q;
} else {
throw new NotSupportedException ("Order By does not support: " + orderExpr);
}
} else {
throw new NotSupportedException ("Must be a predicate");
}
}
private void AddWhere (Expression pred)
{
if (_where == null) {
_where = pred;
} else {
_where = Expression.AndAlso (_where, pred);
}
}
private SQLiteCommand GenerateCommand ()
{
var cmdText = "select * from \"" + Table.TableName + "\"";
var args = new List<object> ();
if (_where != null) {
var w = CompileExpr (_where, args);
cmdText += " where " + w.CommandText;
}
if ((_orderBys != null) && (_orderBys.Count > 0)) {
var t = string.Join (", ", _orderBys.Select (o => "\"" + o.ColumnName + "\"" + (o.Ascending ? "" : " desc")).ToArray ());
cmdText += " order by " + t;
}
if (_limit.HasValue) {
cmdText += " limit " + _limit.Value;
}
if (_offset.HasValue) {
cmdText += " offset " + _limit.Value;
}
return Connection.CreateCommand (cmdText, args.ToArray ());
}
class CompileResult
{
public string CommandText { get; set; }
public object Value { get; set; }
}
private CompileResult CompileExpr (Expression expr, List<object> queryArgs)
{
if (expr == null) {
throw new NotSupportedException ("Expression is NULL");
} else if (expr is BinaryExpression) {
var bin = (BinaryExpression)expr;
var leftr = CompileExpr (bin.Left, queryArgs);
var rightr = CompileExpr (bin.Right, queryArgs);
var text = "(" + leftr.CommandText + " " + GetSqlName (bin) + " " + rightr.CommandText + ")";
return new CompileResult { CommandText = text };
} else if (expr.NodeType == ExpressionType.Call) {
var call = (MethodCallExpression)expr;
var args = new CompileResult[call.Arguments.Count];
for (var i = 0; i < args.Length; i++) {
args[i] = CompileExpr (call.Arguments[i], queryArgs);
}
var sqlCall = "";
if (call.Method.Name == "Like" && args.Length == 2) {
sqlCall = "(" + args[0].CommandText + " like " + args[1].CommandText + ")";
} else {
sqlCall = call.Method.Name.ToLower () + "(" + string.Join (",", args.Select (a => a.CommandText).ToArray ()) + ")";
}
return new CompileResult { CommandText = sqlCall };
} else if (expr.NodeType == ExpressionType.Constant) {
var c = (ConstantExpression)expr;
queryArgs.Add (c.Value);
return new CompileResult {
CommandText = "?",
Value = c.Value
};
} else if (expr.NodeType == ExpressionType.Convert) {
var u = (UnaryExpression)expr;
var ty = u.Type;
var valr = CompileExpr (u.Operand, queryArgs);
return new CompileResult {
CommandText = valr.CommandText,
Value = valr.Value != null ? Convert.ChangeType (valr.Value, ty) : null
};
} else if (expr.NodeType == ExpressionType.MemberAccess) {
var mem = (MemberExpression)expr;
if (mem.Expression.NodeType == ExpressionType.Parameter) {
//
// This is a column of our table, output just the column name
//
return new CompileResult { CommandText = "\"" + mem.Member.Name + "\"" };
} else {
object obj = null;
if (mem.Expression != null) {
var r = CompileExpr (mem.Expression, queryArgs);
if (r.Value == null) {
throw new NotSupportedException ("Member access failed to compile expression");
}
if (r.CommandText == "?") {
queryArgs.RemoveAt (queryArgs.Count - 1);
}
obj = r.Value;
}
if (mem.Member.MemberType == MemberTypes.Property) {
var m = (PropertyInfo)mem.Member;
var val = m.GetValue (obj, null);
queryArgs.Add (val);
return new CompileResult {
CommandText = "?",
Value = val
};
} else if (mem.Member.MemberType == MemberTypes.Field) {
var m = (FieldInfo)mem.Member;
var val = m.GetValue (obj);
queryArgs.Add (val);
return new CompileResult {
CommandText = "?",
Value = val
};
} else {
throw new NotSupportedException ("MemberExpr: " + mem.Member.MemberType.ToString ());
}
}
}
throw new NotSupportedException ("Cannot compile: " + expr.NodeType.ToString ());
}
string GetSqlName (Expression expr)
{
var n = expr.NodeType;
if (n == ExpressionType.GreaterThan)
return ">"; else if (n == ExpressionType.GreaterThanOrEqual) {
return ">=";
} else if (n == ExpressionType.LessThan) {
return "<";
} else if (n == ExpressionType.LessThanOrEqual) {
return "<=";
} else if (n == ExpressionType.And) {
return "and";
} else if (n == ExpressionType.AndAlso) {
return "and";
} else if (n == ExpressionType.Or) {
return "or";
} else if (n == ExpressionType.OrElse) {
return "or";
} else if (n == ExpressionType.Equal) {
return "=";
} else if (n == ExpressionType.NotEqual) {
return "!=";
} else {
throw new System.NotSupportedException ("Cannot get SQL for: " + n.ToString ());
}
}
public IEnumerator<T> GetEnumerator ()
{
return GenerateCommand ().ExecuteQuery<T> ().GetEnumerator ();
}
System.Collections.IEnumerator System.Collections.IEnumerable.GetEnumerator ()
{
return GetEnumerator ();
}
}
public static class SQLite3
{
public enum Result : int
{
OK = 0,
Error = 1,
Internal = 2,
Perm = 3,
Abort = 4,
Busy = 5,
Locked = 6,
NoMem = 7,
ReadOnly = 8,
Interrupt = 9,
IOError = 10,
Corrupt = 11,
NotFound = 12,
TooBig = 18,
Constraint = 19,
Row = 100,
Done = 101
}
public enum ConfigOption : int
{
SingleThread = 1,
MultiThread = 2,
Serialized = 3
}
[DllImport("sqlite3", EntryPoint = "sqlite3_open")]
public static extern Result Open (string filename, out IntPtr db);
[DllImport("sqlite3", EntryPoint = "sqlite3_close")]
public static extern Result Close (IntPtr db);
[DllImport("sqlite3", EntryPoint = "sqlite3_config")]
public static extern Result Config (ConfigOption option);
[DllImport("sqlite3", EntryPoint = "sqlite3_busy_timeout")]
public static extern Result BusyTimeout (IntPtr db, int milliseconds);
[DllImport("sqlite3", EntryPoint = "sqlite3_changes")]
public static extern int Changes (IntPtr db);
[DllImport("sqlite3", EntryPoint = "sqlite3_prepare_v2")]
public static extern Result Prepare2 (IntPtr db, string sql, int numBytes, out IntPtr stmt, IntPtr pzTail);
public static IntPtr Prepare2 (IntPtr db, string query)
{
IntPtr stmt;
var r = Prepare2 (db, query, query.Length, out stmt, IntPtr.Zero);
if (r != Result.OK) {
throw SQLiteException.New (r, GetErrmsg (db));
}
return stmt;
}
[DllImport("sqlite3", EntryPoint = "sqlite3_step")]
public static extern Result Step (IntPtr stmt);
[DllImport("sqlite3", EntryPoint = "sqlite3_finalize")]
public static extern Result Finalize (IntPtr stmt);
[DllImport("sqlite3", EntryPoint = "sqlite3_last_insert_rowid")]
public static extern long LastInsertRowid (IntPtr db);
[DllImport("sqlite3", EntryPoint = "sqlite3_errmsg16")]
public static extern IntPtr Errmsg (IntPtr db);
public static string GetErrmsg (IntPtr db)
{
return Marshal.PtrToStringUni (Errmsg (db));
}
[DllImport("sqlite3", EntryPoint = "sqlite3_bind_parameter_index")]
public static extern int BindParameterIndex (IntPtr stmt, string name);
[DllImport("sqlite3", EntryPoint = "sqlite3_bind_null")]
public static extern int BindNull (IntPtr stmt, int index);
[DllImport("sqlite3", EntryPoint = "sqlite3_bind_int")]
public static extern int BindInt (IntPtr stmt, int index, int val);
[DllImport("sqlite3", EntryPoint = "sqlite3_bind_int64")]
public static extern int BindInt64 (IntPtr stmt, int index, long val);
[DllImport("sqlite3", EntryPoint = "sqlite3_bind_double")]
public static extern int BindDouble (IntPtr stmt, int index, double val);
[DllImport("sqlite3", EntryPoint = "sqlite3_bind_text")]
public static extern int BindText (IntPtr stmt, int index, string val, int n, IntPtr free);
[DllImport("sqlite3", EntryPoint = "sqlite3_column_count")]
public static extern int ColumnCount (IntPtr stmt);
[DllImport("sqlite3", EntryPoint = "sqlite3_column_name")]
public static extern IntPtr ColumnName (IntPtr stmt, int index);
[DllImport("sqlite3", EntryPoint = "sqlite3_column_name16")]
public static extern IntPtr ColumnName16 (IntPtr stmt, int index);
[DllImport("sqlite3", EntryPoint = "sqlite3_column_type")]
public static extern ColType ColumnType (IntPtr stmt, int index);
[DllImport("sqlite3", EntryPoint = "sqlite3_column_int")]
public static extern int ColumnInt (IntPtr stmt, int index);
[DllImport("sqlite3", EntryPoint = "sqlite3_column_int64")]
public static extern long ColumnInt64 (IntPtr stmt, int index);
[DllImport("sqlite3", EntryPoint = "sqlite3_column_double")]
public static extern double ColumnDouble (IntPtr stmt, int index);
[DllImport("sqlite3", EntryPoint = "sqlite3_column_text")]
public static extern IntPtr ColumnText (IntPtr stmt, int index);
[DllImport("sqlite3", EntryPoint = "sqlite3_column_text16")]
public static extern IntPtr ColumnText16 (IntPtr stmt, int index);
public static string ColumnString (IntPtr stmt, int index)
{
return Marshal.PtrToStringUni (SQLite3.ColumnText16 (stmt, index));
}
public enum ColType : int
{
Integer = 1,
Float = 2,
Text = 3,
Blob = 4,
Null = 5
}
}
}