/// <summary>
/// Appends the current property name, e.g. <c>"Item.MyValue"</c>, to the attribute buffer.
/// </summary>
/// <param name="attribute">The current attribute</param>
/// <param name="tblAlias">An alias to qualify the property name with.</param>
/// <param name="propName">A name to suffix the property name with.</param>
/// <returns>A new attribute containing the appended buffer.</returns>
public static IProjectionAttribute Prop(this IProjectionAttribute attribute, string tblAlias = null, string propName = null)
{
if ((propName == null || attribute.Field != null) && attribute.Metadata.HasFlag(RelationMetadataFlags.Model))
{
throw ProjectionException.FromProjection(attribute, "Cannot reference model directly.");
}
if (attribute.Field != null)
{
IField field = attribute.Field();
ColumnBinding binding = new ColumnBinding(field.Identity.Name, field);
propName = attribute.Context.Domain.Dialect.Identifier(binding.ColumnName);
return(attribute.Append(propName).Append(binding));
}
else
{
string fullName = attribute.Metadata.Identity.Name;
if (propName != null)
{
fullName = attribute.Identity.Schema.Notation.Combine(fullName, propName);
}
if (tblAlias != null)
{
attribute = attribute.Append(attribute.Context.Domain.Dialect.Identifier(tblAlias));
attribute = attribute.Append(attribute.Context.Domain.Dialect.Qualifier);
}
return(attribute.Append(attribute.Context.Domain.Dialect.Identifier(fullName)));
}
}
/// <summary>
/// Appends the current parameter name and value, e.g. <c>@P0</c>, to the attribute buffer.
/// </summary>
/// <param name="attribute">The current attribute.</param>
/// <returns>A new attribute containing the appended buffer.</returns>
public static IProjectionAttribute Par(this IProjectionAttribute attribute)
{
if (!attribute.Context.Domain.Dialect.Support.HasFlag(DialectSupport.InputParameters))
{
throw ProjectionException.FromProjection(attribute, $"Dialect '{attribute.Context.Domain.Dialect.GetType().Name}' does not support input parameters.");
}
IField value = attribute.Field?.Invoke();
if (value != null)
{
string paramName = attribute.Context.Lookup.Parameter(attribute.Identity, value);
string dialectName = attribute.Context.Domain.Dialect.Parameter(paramName);
Parameter param = new Parameter(paramName, value);
IProjectionAttribute result = attribute.Append(dialectName).Append(param);
if (attribute.Metadata.HasFlag(ProjectionMetadataFlags.Output) && attribute.Context.Domain.Dialect.Support.HasFlag(DialectSupport.OutputParameters))
{
ParameterBinding binding = new ParameterBinding(param);
result = result.Append(binding);
}
return(result);
}
else
{
string paramName = attribute.Context.Lookup.Parameter(attribute.Identity, attribute.Metadata.Identity);
string dialectName = attribute.Context.Domain.Dialect.Parameter(paramName);
return(attribute.Append(dialectName));
}
}
public static IProjectionMetadata GetPreferredTvpMetadata(IProjection projection)
{
if (projection.Metadata.List == null && projection.Metadata.Item == null)
{
throw ProjectionException.FromProjection(projection, "No table information found.");
}
return(projection.Metadata.List ?? projection.Metadata.Item?.List);
}
/// <summary>
/// Navigates the current projection to its default item target.
/// </summary>
/// <param name="projection">The current projection.</param>
/// <returns>A new projection of the item target.</returns>
public static IProjection Open(this IProjection projection)
{
if (!projection.Metadata.HasFlag(RelationMetadataFlags.List))
{
throw ProjectionException.FromProjection(projection, "No metadata list contract found.");
}
return(projection.With(metadata: projection.Metadata.Item));
}
/// <summary>
/// Appends mappings between the current qualified columns and their properties, e.g. <c>T0."MyColumn" AS "Item.MyValue"</c>, to the projection buffer. Identical to calling <c>Cols().As().Props()</c>.
/// </summary>
/// <param name="projection">The current projection</param>
/// <returns>A new projection containing the appended buffer.</returns>
public static IProjection Star(this IProjection projection)
{
if (!projection.Any())
{
throw ProjectionException.FromProjection(projection, "No attributes found.");
}
IProjectionMetadata metadata = ProjectionHelper.GetPreferredTableMetadata(projection).Identity.GetMetadata <IProjectionMetadata>();
return(projection.With(metadata).Cols().As().Props());
}
/// <summary>
/// Appends the current JSON path literal, e.g. <c>'$.my.value'</c>, to the attribute buffer.
/// </summary>
/// <param name="attribute">The current attribute.</param>
/// <returns>A new attribute containing the appended buffer.</returns>
public static IProjectionAttribute JsonPath(this IProjectionAttribute attribute)
{
IJsonMetadata metadata = attribute.Metadata.Identity.GetMetadata <IJsonMetadata>();
if (metadata == null)
{
throw ProjectionException.FromProjection(attribute, "JSON metadata not found.");
}
string literal = attribute.Context.Domain.Dialect.String(metadata.Path);
return(attribute.Append(literal));
}
public static ITableMetadata GetPreferredColumnMetadata(IProjectionAttribute attribute)
{
if (attribute.Metadata.HasFlag(TableMetadataFlags.Column))
{
return(attribute.Metadata.Table);
}
else if (attribute.Metadata.Item != null && attribute.Metadata.Item.HasFlag(TableMetadataFlags.Column))
{
return(attribute.Metadata.Item.Table);
}
throw ProjectionException.FromProjection(attribute, "No column information found.");
}
/// <summary>
/// Appends a table-valued parameter from the current values, e.g. <c>@TP0</c>, to the projection buffer.
/// </summary>
/// <param name="projection">The current projection.</param>
/// <returns>A new attribute containing the appended buffer.</returns>
public static IProjectionAttribute TvpName(this IProjection projection)
{
if (projection.Source == null)
{
throw ProjectionException.ValueNotFound(projection);
}
else if (!projection.Attributes.Any())
{
throw ProjectionException.FromProjection(projection, "No attributes found.");
}
Relation relation = new Relation(projection.Source, projection.Attributes.Select(a => a.Metadata.Identity));
string paramName = projection.Context.Lookup.Custom("TP", projection.Identity, field: projection.Source);
string dialectName = projection.Context.Domain.Dialect.Parameter(paramName);
return(projection.Attr().Append(dialectName).Append(new TableValuedParameter(paramName, relation)));
}
/// <summary>
/// Appends a call to <c>JSON_VALUE</c> from the current column and JSON path, e.g. <c>JSON_VALUE(T0."MyJson", '$.my.value')</c>, to the attribute buffer.
/// </summary>
/// <param name="attribute">The current attribute.</param>
/// <returns>A new attribute containing the appended buffer.</returns>
public static IProjectionAttribute Json(this IProjectionAttribute attribute)
{
IJsonMetadata json = ProjectionHelper.GetJsonMetadata(attribute);
IProjectionMetadata metadata = attribute.Metadata;
IProjectionMetadata rootMetadata = json.MemberOf.Identity.GetMetadata <IProjectionMetadata>();
attribute = attribute.Append("JSON_VALUE(");
try
{
attribute = attribute.With(metadata: rootMetadata).Col();
}
catch (ProjectionException ex)
{
throw ProjectionException.FromProjection(attribute, "JSON value requires a column to read from.", innerException: ex);
}
attribute = attribute.Append(",");
attribute = attribute.With(metadata: metadata).JsonPath();
attribute = attribute.Append(")");
return(attribute);
}
/// <summary>
/// Appends a table-valued parameter from the current values, e.g. <c>@TP0</c>, to the projection buffer.
/// </summary>
/// <param name="projection">The current projection.</param>
/// <returns>A new attribute containing the appended buffer.</returns>
public static IProjectionAttribute TvpName(this IProjection projection)
{
if (projection.Source == null)
{
throw ProjectionException.ValueNotFound(projection);
}
else if (!projection.Attributes.Any())
{
throw ProjectionException.FromProjection(projection, "No attributes found.");
}
IProjectionMetadata metadata = TvpHelper.GetPreferredTvpMetadata(projection);
IField source = new Relation(projection.Source, metadata.Identity.Name).Scalar();
RelationIdentity identity = new RelationIdentity(metadata.Identity.Schema, projection.Attributes.Select(a => a.Metadata.Identity));
IBindingParameterContract contract = TvpCache.GetParameterContract(identity);
string paramName = projection.Context.Lookup.Custom("TP", projection.Identity, field: source);
string dialectName = projection.Context.Domain.Dialect.Parameter(paramName);
return(projection.Attr().Append(dialectName).Append(new Parameter(paramName, source, contract)));
}
public static IJsonMetadata GetJsonMetadata(IProjectionAttribute attribute) => attribute.Metadata.Identity.GetMetadata <IJsonMetadata>() ?? throw ProjectionException.FromProjection(attribute, "JSON metadata not found.");
public static IProjectionMetadata GetMetadataFromRelativeLambda(IProjection projection, LambdaExpression expression)
{
if (expression == null)
{
throw new ArgumentNullException(nameof(expression));
}
string name = projection.Metadata.Identity.Notation.Lambda(expression);
string fullName = projection.Metadata.Identity.Notation.Combine(projection.Metadata.Identity.Name, name);
return(projection.Metadata.Identity.Schema.GetMetadata <IProjectionMetadata>(fullName) ?? throw ProjectionException.FromProjection(projection, "Metadata not found."));
}
public static ITableMetadata GetPreferredTableMetadata(IProjectionAttribute attribute) => GetPreferredTableMetadata(attribute.Metadata) ?? throw ProjectionException.FromProjection(attribute, "No table information found.");
public static ITableMetadata GetPreferredTableMetadata(IProjection projection) => GetPreferredTableMetadata(projection.Metadata) ?? throw ProjectionException.FromProjection(projection, "No table information found.");