private SqlExpression GetFirstArgumentAsInt64(IReadOnlyList <SqlExpression> arguments, long multiplier)
{
SqlExpression value = _sqlExpressionFactory.ApplyDefaultTypeMapping(arguments[0]);
if (value.TypeMapping != null && value.TypeMapping.StoreTypeNameBase == "FLOAT64")
{
value = _sqlExpressionFactory.ApplyDefaultTypeMapping(_sqlExpressionFactory.Function("CAST", new[] { value, _sqlExpressionFactory.Fragment("INT64") }, typeof(long)));
}
if (multiplier != 1L)
{
value = _sqlExpressionFactory.Multiply(_sqlExpressionFactory.Constant(multiplier), value, value.TypeMapping);
}
return(value);
}
public virtual SqlExpression Translate(SqlExpression instance, MemberInfo member, Type returnType)
{
Check.NotNull(member, nameof(member));
Check.NotNull(returnType, nameof(returnType));
if (member.DeclaringType == typeof(DateTime))
{
var memberName = member.Name;
if (_datePartMapping.TryGetValue(memberName, out var datePart))
{
return(_sqlExpressionFactory.Convert(
SqliteExpression.Strftime(
_sqlExpressionFactory,
typeof(string),
datePart,
instance),
returnType));
}
if (string.Equals(memberName, nameof(DateTime.Ticks)))
{
return(_sqlExpressionFactory.Convert(
_sqlExpressionFactory.Multiply(
_sqlExpressionFactory.Subtract(
_sqlExpressionFactory.Function(
"julianday",
new[] { instance },
nullable: true,
argumentsPropagateNullability: new[] { true },
typeof(double)),
_sqlExpressionFactory.Constant(1721425.5)), // NB: Result of julianday('0001-01-01 00:00:00')
_sqlExpressionFactory.Constant(TimeSpan.TicksPerDay)),
typeof(long)));
}
if (string.Equals(memberName, nameof(DateTime.Millisecond)))
{
return(_sqlExpressionFactory.Modulo(
_sqlExpressionFactory.Multiply(
_sqlExpressionFactory.Convert(
SqliteExpression.Strftime(
_sqlExpressionFactory,
typeof(string),
"%f",
instance),
typeof(double)),
_sqlExpressionFactory.Constant(1000)),
_sqlExpressionFactory.Constant(1000)));
}
var format = "%Y-%m-%d %H:%M:%f";
SqlExpression timestring;
var modifiers = new List <SqlExpression>();
switch (memberName)
{
case nameof(DateTime.Now):
timestring = _sqlExpressionFactory.Constant("now");
modifiers.Add(_sqlExpressionFactory.Constant("localtime"));
break;
case nameof(DateTime.UtcNow):
timestring = _sqlExpressionFactory.Constant("now");
break;
case nameof(DateTime.Date):
timestring = instance;
modifiers.Add(_sqlExpressionFactory.Constant("start of day"));
break;
case nameof(DateTime.Today):
timestring = _sqlExpressionFactory.Constant("now");
modifiers.Add(_sqlExpressionFactory.Constant("localtime"));
modifiers.Add(_sqlExpressionFactory.Constant("start of day"));
break;
case nameof(DateTime.TimeOfDay):
format = "%H:%M:%f";
timestring = instance;
break;
default:
return(null);
}
Check.DebugAssert(timestring != null, "timestring is null");
return(_sqlExpressionFactory.Function(
"rtrim",
new SqlExpression[]
{
_sqlExpressionFactory.Function(
"rtrim",
new SqlExpression[]
{
SqliteExpression.Strftime(
_sqlExpressionFactory,
returnType,
format,
timestring,
modifiers),
_sqlExpressionFactory.Constant("0")
},
nullable: true,
argumentsPropagateNullability: new[] { true, false },
returnType),
_sqlExpressionFactory.Constant(".")
},
nullable: true,
argumentsPropagateNullability: new[] { true, false },
returnType));
}
return(null);
}
private static SqlExpression GetAndoyerDistance(
SqlExpression left,
SqlExpression right,
Type resultType,
ISqlExpressionFactory sqlExpressionFactory)
{
SqlExpression toDegrees(SqlExpression coord)
=> sqlExpressionFactory.Divide(
sqlExpressionFactory.Multiply(
coord,
sqlExpressionFactory.Function(
"PI",
Array.Empty <SqlExpression>(),
resultType)),
sqlExpressionFactory.Constant(180.0));
SqlExpression xCoord(SqlExpression point)
=> sqlExpressionFactory.Function(
"ST_X",
new[] { point },
resultType);
SqlExpression yCoord(SqlExpression point)
=> sqlExpressionFactory.Function(
"ST_Y",
new[] { point },
resultType);
var c0 = sqlExpressionFactory.Constant(0.0);
var c1 = sqlExpressionFactory.Constant(1.0);
var c2 = sqlExpressionFactory.Constant(2.0);
var c3 = sqlExpressionFactory.Constant(3.0);
var c2Int = sqlExpressionFactory.Constant(2);
var lon1 = toDegrees(xCoord(left));
var lat1 = toDegrees(yCoord(left));
var lon2 = toDegrees(xCoord(right));
var lat2 = toDegrees(yCoord(right));
var g = sqlExpressionFactory.Divide(
sqlExpressionFactory.Subtract(
lat1,
lat2),
c2);
var lambda = sqlExpressionFactory.Divide(
sqlExpressionFactory.Subtract(
lon1,
lon2),
c2);
var f = sqlExpressionFactory.Divide(
sqlExpressionFactory.Add(
lat1,
lat2),
c2);
var sinG2 = sqlExpressionFactory.Function(
"POWER",
new SqlExpression[]
{
sqlExpressionFactory.Function(
"SIN",
new[] { g },
resultType),
c2Int
},
resultType);
var cosG2 = sqlExpressionFactory.Function(
"POWER",
new SqlExpression[]
{
sqlExpressionFactory.Function(
"COS",
new[] { g },
resultType),
c2Int
},
resultType);
var sinF2 = sqlExpressionFactory.Function(
"POWER",
new SqlExpression[]
{
sqlExpressionFactory.Function(
"SIN",
new[] { f },
resultType),
c2Int
},
resultType);
var cosF2 = sqlExpressionFactory.Function(
"POWER",
new SqlExpression[]
{
sqlExpressionFactory.Function(
"COS",
new[] { f },
resultType),
c2Int
},
resultType);
var sinL2 = sqlExpressionFactory.Function(
"POWER",
new SqlExpression[]
{
sqlExpressionFactory.Function(
"SIN",
new[] { lambda },
resultType),
c2Int
},
resultType);
var cosL2 = sqlExpressionFactory.Function(
"POWER",
new SqlExpression[]
{
sqlExpressionFactory.Function(
"COS",
new[] { lambda },
resultType),
c2Int
},
resultType);
var s = sqlExpressionFactory.Add(
sqlExpressionFactory.Multiply(sinG2, cosL2),
sqlExpressionFactory.Multiply(cosF2, sinL2));
var c = sqlExpressionFactory.Add(
sqlExpressionFactory.Multiply(cosG2, cosL2),
sqlExpressionFactory.Multiply(sinF2, sinL2));
var radiusA = sqlExpressionFactory.Constant(6378137.0);
var radiusB = sqlExpressionFactory.Constant(6356752.3142451793);
var flattening = sqlExpressionFactory.Divide(
sqlExpressionFactory.Subtract(radiusA, radiusB),
radiusA);
var omega = sqlExpressionFactory.Function(
"ATAN",
new[]
{
sqlExpressionFactory.Function(
"SQRT",
new[] { sqlExpressionFactory.Divide(s, c) },
resultType)
},
resultType);
var r3 = sqlExpressionFactory.Divide(
sqlExpressionFactory.Multiply(
c3,
sqlExpressionFactory.Function(
"SQRT",
new[] { sqlExpressionFactory.Multiply(s, c) },
resultType)),
omega);
var d = sqlExpressionFactory.Multiply(
sqlExpressionFactory.Multiply(c2, omega),
radiusA);
var h1 = sqlExpressionFactory.Divide(
sqlExpressionFactory.Subtract(r3, c1),
sqlExpressionFactory.Multiply(c2, c));
var h2 = sqlExpressionFactory.Divide(
sqlExpressionFactory.Add(r3, c1),
sqlExpressionFactory.Multiply(c2, s));
var andoyer = sqlExpressionFactory.Multiply(
d,
sqlExpressionFactory.Add(
c1,
sqlExpressionFactory.Multiply(
flattening,
sqlExpressionFactory.Subtract(
sqlExpressionFactory.Multiply(
sqlExpressionFactory.Multiply(
h1,
sinF2),
cosG2),
sqlExpressionFactory.Multiply(
sqlExpressionFactory.Multiply(
h2,
cosF2),
sinG2)))));
return(sqlExpressionFactory.Case(
new[]
{
new CaseWhenClause(
sqlExpressionFactory.OrElse(
sqlExpressionFactory.OrElse(
sqlExpressionFactory.AndAlso(
sqlExpressionFactory.Equal(lambda, c0),
sqlExpressionFactory.Equal(g, c0)),
sqlExpressionFactory.Equal(s, c0)),
sqlExpressionFactory.Equal(c, c0)),
c0),
},
andoyer));
}
private static SqlExpression GetHaversineDistance(
SqlExpression left,
SqlExpression right,
Type resultType,
ISqlExpressionFactory sqlExpressionFactory)
{
// HAVERSINE = 6371000 * 2 * ASIN(
// SQRT(
// POWER(SIN((ST_Y(pt2) - ST_Y(pt1)) * pi()/180 / 2), 2) +
// COS(ST_Y(pt1) * pi()/180) *
// COS(ST_Y(pt2) * pi()/180) *
// POWER(SIN((ST_X(pt2) - ST_X(pt1)) * pi()/180 / 2), 2)
// )
// )
return(sqlExpressionFactory.Multiply(
sqlExpressionFactory.Constant(6370986.0), // see https://postgis.net/docs/manual-1.4/ST_Distance_Sphere.html
sqlExpressionFactory.Multiply(
sqlExpressionFactory.Constant(2.0),
sqlExpressionFactory.Function(
"ASIN",
new[]
{
sqlExpressionFactory.Function(
"SQRT",
new[]
{
sqlExpressionFactory.Add(
sqlExpressionFactory.Function(
"POWER",
new SqlExpression[]
{
sqlExpressionFactory.Function(
"SIN",
new[]
{
sqlExpressionFactory.Divide(
sqlExpressionFactory.Divide(
sqlExpressionFactory.Multiply(
sqlExpressionFactory.Subtract(
sqlExpressionFactory.Function(
"ST_Y",
new[] { right },
resultType),
sqlExpressionFactory.Function(
"ST_Y",
new[] { left },
resultType)),
sqlExpressionFactory.Function(
"PI",
Array.Empty <SqlExpression>(),
resultType)),
sqlExpressionFactory.Constant(180.0)),
sqlExpressionFactory.Constant(2.0))
},
resultType),
sqlExpressionFactory.Constant(2),
},
resultType),
sqlExpressionFactory.Multiply(
sqlExpressionFactory.Function(
"COS",
new[]
{
sqlExpressionFactory.Divide(
sqlExpressionFactory.Multiply(
sqlExpressionFactory.Function(
"ST_Y",
new[] { left },
resultType),
sqlExpressionFactory.Function(
"PI",
Array.Empty <SqlExpression>(),
resultType)),
sqlExpressionFactory.Constant(180.0)),
},
resultType),
sqlExpressionFactory.Multiply(
sqlExpressionFactory.Function(
"COS",
new[]
{
sqlExpressionFactory.Divide(
sqlExpressionFactory.Multiply(
sqlExpressionFactory.Function(
"ST_Y",
new[] { right },
resultType),
sqlExpressionFactory.Function(
"PI",
Array.Empty <SqlExpression>(),
resultType)),
sqlExpressionFactory.Constant(180.0)),
},
resultType),
sqlExpressionFactory.Function(
"POWER",
new SqlExpression[]
{
sqlExpressionFactory.Function(
"SIN",
new[]
{
sqlExpressionFactory.Divide(
sqlExpressionFactory.Divide(
sqlExpressionFactory.Multiply(
sqlExpressionFactory.Subtract(
sqlExpressionFactory.Function(
"ST_X",
new[] { right },
resultType),
sqlExpressionFactory.Function(
"ST_X",
new[] { left },
resultType)),
sqlExpressionFactory.Function(
"PI",
Array.Empty <SqlExpression>(),
resultType)),
sqlExpressionFactory.Constant(180.0)),
sqlExpressionFactory.Constant(2.0))
},
resultType),
sqlExpressionFactory.Constant(2),
},
resultType))))
},
resultType)
},
resultType))));
}
