public SqlExpression MakeIndexOfExpression(
[NotNull] SqlExpression target,
[NotNull] SqlExpression search,
[CanBeNull] SqlExpression stringComparison = null)
{
if (stringComparison == null)
{
return(MakeIndexOfExpressionImpl(
target,
e => e,
search,
e => e));
}
// Users have to opt-in, to use string method translations with an explicit StringComparison parameter.
if (!_options.StringComparisonTranslations)
{
return(null);
}
if (TryGetExpressionValue <StringComparison>(stringComparison, out var cmp))
{
return(CreateExpressionForCaseSensitivity(
cmp,
() => MakeIndexOfExpressionImpl(
target,
e => e,
search,
e => Utf8Bin(e)),
() => MakeIndexOfExpressionImpl(
target,
e => LCase(e),
search,
e => Utf8Bin(LCase(e)))));
}
return(_sqlExpressionFactory.Case(
new[]
{
new CaseWhenClause(
_sqlExpressionFactory.In(
stringComparison,
_caseSensitiveComparisons,
false),
// Case sensitive, accent sensitive
MakeIndexOfExpressionImpl(
target,
e => e,
search,
e => Utf8Bin(e)))
},
// Case insensitive, accent sensitive
MakeIndexOfExpressionImpl(
target,
e => LCase(e),
search,
e => Utf8Bin(LCase(e)))));
}
public SqlExpression MakeIndexOfExpression(
[NotNull] SqlExpression target,
[NotNull] SqlExpression search,
[CanBeNull] SqlExpression stringComparison = null)
{
if (stringComparison == null)
{
return(MakeIndexOfExpressionImpl(
target,
e => e,
search,
e => e));
}
if (TryGetExpressionValue <StringComparison>(stringComparison, out var cmp))
{
return(CreateExpressionForCaseSensitivity(
cmp,
() => MakeIndexOfExpressionImpl(
target,
e => e,
search,
e => Utf8Bin(e)),
() => MakeIndexOfExpressionImpl(
target,
e => LCase(e),
search,
e => Utf8Bin(LCase(e)))));
}
return(_sqlExpressionFactory.Case(
new[]
{
new CaseWhenClause(
_sqlExpressionFactory.In(
stringComparison,
_caseSensitiveComparisons,
false),
// Case sensitive, accent sensitive
MakeIndexOfExpressionImpl(
target,
e => e,
search,
e => Utf8Bin(e)))
},
// Case insensitive, accent sensitive
MakeIndexOfExpressionImpl(
target,
e => LCase(e),
search,
e => Utf8Bin(LCase(e)))));
}
private SqlExpression MakeIndexOfExpression(
[NotNull] SqlExpression target,
[NotNull] SqlExpression search,
[NotNull] SqlExpression stringComparison)
{
if (TryGetExpressionValue <StringComparison>(stringComparison, out var cmp))
{
return(CreateExpressionForCaseSensitivity(
cmp,
() =>
MakeIndexOfExpressionImpl(
target,
Utf8Bin(search)
),
() =>
MakeIndexOfExpressionImpl(
LCase(target),
Utf8Bin(LCase(search))
)
));
}
else
{
return(_sqlExpressionFactory.Case(
new[]
{
new CaseWhenClause(
_sqlExpressionFactory.In(stringComparison, _caseSensitiveComparisons, false),
// Case sensitive, accent sensitive
MakeIndexOfExpressionImpl(
target,
Utf8Bin(search)
)
)
},
// Case insensitive, accent sensitive
MakeIndexOfExpressionImpl(
LCase(target),
Utf8Bin(LCase(search))
)
));
}
}
/// <summary>
/// This API supports the Entity Framework Core infrastructure and is not intended to be used
/// directly from your code. This API may change or be removed in future releases.
/// </summary>
public virtual SqlExpression Translate(SqlExpression instance, MethodInfo method, IReadOnlyList <SqlExpression> arguments, IDiagnosticsLogger <DbLoggerCategory.Query> logger)
{
if (Equals(method, _spatialDistancePlanarMethodInfo))
{
// MySQL 8 uses the Andoyer algorithm by default for `ST_Distance()`, if an SRID of 4326 has been
// associated with the geometry.
// Since this call explicitly asked for a planar distance calculation, we need to ensure that
// MySQL actually does that.
// MariaDB ignores SRIDs and always calculates the planar distance.
// CHECK: It could be faster to just manually apply the Pythagoras Theorem instead of changing the
// SRID in the case where ST_SRID() does not support a second parameter yet (see
// SetSrid()).
if (_options.ServerVersion.Supports.SpatialSupportFunctionAdditions &&
_options.ServerVersion.Supports.SpatialDistanceFunctionImplementsAndoyer)
{
return(_sqlExpressionFactory.Case(
new[]
{
new CaseWhenClause(
_sqlExpressionFactory.Equal(
_sqlExpressionFactory.NullableFunction(
"ST_SRID",
new[] { arguments[1] },
typeof(int)),
_sqlExpressionFactory.Constant(0)),
GetStDistanceFunctionCall(
arguments[1],
arguments[2],
method.ReturnType,
_typeMappingSource.FindMapping(method.ReturnType),
_sqlExpressionFactory))
},
GetStDistanceFunctionCall(
SetSrid(arguments[1], 0, _sqlExpressionFactory, _options),
SetSrid(arguments[2], 0, _sqlExpressionFactory, _options),
method.ReturnType,
_typeMappingSource.FindMapping(method.ReturnType),
_sqlExpressionFactory)));
}
return(GetStDistanceFunctionCall(
arguments[1],
arguments[2],
method.ReturnType,
_typeMappingSource.FindMapping(method.ReturnType),
_sqlExpressionFactory));
}
if (Equals(method, _spatialDistanceSphere))
{
if (!(arguments[3] is SqlConstantExpression algorithm))
{
throw new InvalidOperationException("The 'algorithm' parameter must be supplied as a constant.");
}
return(GetStDistanceSphereFunctionCall(
arguments[1],
arguments[2],
(SpatialDistanceAlgorithm)algorithm.Value,
method.ReturnType,
_typeMappingSource.FindMapping(method.ReturnType),
_sqlExpressionFactory,
_options));
}
return(null);
}
private static SqlExpression GetAndoyerDistance(
SqlExpression left,
SqlExpression right,
Type resultType,
MySqlSqlExpressionFactory sqlExpressionFactory)
{
SqlExpression toDegrees(SqlExpression coord)
=> sqlExpressionFactory.Divide(
sqlExpressionFactory.Multiply(
coord,
sqlExpressionFactory.NonNullableFunction(
"PI",
Array.Empty <SqlExpression>(),
resultType)),
sqlExpressionFactory.Constant(180.0));
SqlExpression xCoord(SqlExpression point)
=> sqlExpressionFactory.NullableFunction(
"ST_X",
new[] { point },
resultType);
SqlExpression yCoord(SqlExpression point)
=> sqlExpressionFactory.NullableFunction(
"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.NullableFunction(
"POWER",
new SqlExpression[]
{
sqlExpressionFactory.NullableFunction(
"SIN",
new[] { g },
resultType),
c2Int
},
resultType);
var cosG2 = sqlExpressionFactory.NullableFunction(
"POWER",
new SqlExpression[]
{
sqlExpressionFactory.NullableFunction(
"COS",
new[] { g },
resultType),
c2Int
},
resultType);
var sinF2 = sqlExpressionFactory.NullableFunction(
"POWER",
new SqlExpression[]
{
sqlExpressionFactory.NullableFunction(
"SIN",
new[] { f },
resultType),
c2Int
},
resultType);
var cosF2 = sqlExpressionFactory.NullableFunction(
"POWER",
new SqlExpression[]
{
sqlExpressionFactory.NullableFunction(
"COS",
new[] { f },
resultType),
c2Int
},
resultType);
var sinL2 = sqlExpressionFactory.NullableFunction(
"POWER",
new SqlExpression[]
{
sqlExpressionFactory.NullableFunction(
"SIN",
new[] { lambda },
resultType),
c2Int
},
resultType);
var cosL2 = sqlExpressionFactory.NullableFunction(
"POWER",
new SqlExpression[]
{
sqlExpressionFactory.NullableFunction(
"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.NullableFunction(
"ATAN",
new[]
{
sqlExpressionFactory.NullableFunction(
"SQRT",
new[] { sqlExpressionFactory.Divide(s, c) },
resultType,
false)
},
resultType);
var r3 = sqlExpressionFactory.Divide(
sqlExpressionFactory.Multiply(
c3,
sqlExpressionFactory.NullableFunction(
"SQRT",
new[] { sqlExpressionFactory.Multiply(s, c) },
resultType,
false)),
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));
}
public static SqlExpression GetStDistanceSphereFunctionCall(
SqlExpression left,
SqlExpression right,
SpatialDistanceAlgorithm algorithm,
Type resultType,
RelationalTypeMapping resultTypeMapping,
MySqlSqlExpressionFactory sqlExpressionFactory,
IMySqlOptions options)
{
if (options.ServerVersion.Supports.SpatialDistanceSphereFunction)
{
if (algorithm == SpatialDistanceAlgorithm.Native)
{
// Returns null for empty geometry arguments.
return(sqlExpressionFactory.NullableFunction(
"ST_Distance_Sphere",
new[] { left, right },
resultType,
resultTypeMapping,
false));
}
if (algorithm == SpatialDistanceAlgorithm.Andoyer &&
options.ServerVersion.Supports.SpatialDistanceFunctionImplementsAndoyer)
{
// The `ST_Distance()` in MySQL already uses the Andoyer algorithm, when SRID 4326 is associated
// with the geometry.
// CHECK: It might be faster to just run the custom implementation, if `ST_SRID()` does not support
// a second parameter yet (see SetSrid()).
return(sqlExpressionFactory.Case(
new[]
{
new CaseWhenClause(
sqlExpressionFactory.Equal(
sqlExpressionFactory.NullableFunction(
"ST_SRID",
new[] { left },
typeof(int)),
sqlExpressionFactory.Constant(4326)),
GetStDistanceFunctionCall(
left,
right,
resultType,
resultTypeMapping,
sqlExpressionFactory))
},
GetStDistanceFunctionCall(
SetSrid(left, 4326, sqlExpressionFactory, options),
SetSrid(right, 4326, sqlExpressionFactory, options),
resultType,
resultTypeMapping,
sqlExpressionFactory)));
}
if (algorithm == SpatialDistanceAlgorithm.Haversine)
{
// The Haversine algorithm assumes planar coordinates.
return(sqlExpressionFactory.Case(
new[]
{
new CaseWhenClause(
sqlExpressionFactory.Equal(
sqlExpressionFactory.NullableFunction(
"ST_SRID",
new[] { left },
typeof(int)),
sqlExpressionFactory.Constant(0)),
GetHaversineDistance(
left,
right,
resultType,
sqlExpressionFactory))
},
GetHaversineDistance(
SetSrid(left, 0, sqlExpressionFactory, options),
SetSrid(right, 0, sqlExpressionFactory, options),
resultType,
sqlExpressionFactory)));
}
}
if (algorithm == SpatialDistanceAlgorithm.Haversine)
{
return(GetHaversineDistance(left, right, resultType, sqlExpressionFactory));
}
return(GetAndoyerDistance(left, right, resultType, sqlExpressionFactory));
}