public static IProjectionAttribute ValList(this IProjection projection, Func <IProjectionAttribute, IProjectionAttribute> itemFactory)
{
if (projection.Data == null)
{
throw ProjectionException.ValueNotFound(projection.Metadata);
}
IProjectionMetadata itemMetadata = projection.Metadata?.Item ?? projection.Metadata;
using ProjectionReader reader = new ProjectionReader(projection.Data.Source, new[] { itemMetadata });
IProjectionAttribute attribute = new ProjectionAttribute(projection.Identity, projection.Context, itemMetadata, data: null);
if (reader.Read())
{
IProjectionData data = reader.GetData().First();
attribute = itemFactory(attribute.With(data: data));
}
while (reader.Read())
{
IProjectionData data = reader.GetData().First();
attribute = attribute.Append(", ");
attribute = itemFactory(attribute.With(data: data));
}
return(attribute);
}
public static IProjectionValues <TModel> Vals <TModel>(this IProjection <TModel> projection, int batchIndex = -1)
{
if (projection.Data == null)
{
throw ProjectionException.ValueNotFound(projection.Metadata);
}
else if (projection.Data.Source.Snapshot == null)
{
IEnumerable <IProjection <TModel> > emptyItems = Array.Empty <IProjection <TModel> >();
return(new ProjectionValues <TModel>(projection.Context, projection.Identity, emptyItems, batchIndex));
}
IProjectionMetadata[] header = new[] { projection.Metadata }.Concat(projection.Header.Select(a => a.Metadata)).ToArray();
IProjectionAttribute[] attributes = header.Skip(1).Select(m => new ProjectionAttribute(projection.Identity, projection.Context, m, data: null)).ToArray();
return(new ProjectionValues <TModel>(projection.Context, projection.Identity, innerReader(), batchIndex));
IEnumerable <IProjection <TModel> > innerReader()
{
using ProjectionReader reader = new ProjectionReader(projection.Data.Source, header);
while (reader.Read())
{
IProjectionData[] dataSet = reader.GetData().ToArray();
if (dataSet[0].Source.Snapshot != null)
{
IEnumerable <IProjectionAttribute> valueHeader = attributes.Zip(dataSet.Skip(1)).Select(t => t.First.With(data: t.Second));
yield return(projection.With(data: dataSet[0], header: valueHeader));
}
}
}
}
public static IField GetFieldValue(IProjectionAttribute attribute)
{
if (attribute.Field == null)
{
throw ProjectionException.ValueNotFound(attribute);
}
return(attribute.Field());
}
public static IProjection Val(this IProjection projection)
{
IProjection value = projection.Vals().FirstOrDefault();
if (value == null)
{
throw ProjectionException.ValueNotFound(projection);
}
return(value);
}
/// <summary>
/// Appends the current variable name, e.g. <c>@V0</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 Var(this IProjectionAttribute attribute)
{
if (attribute.Data == null)
{
throw ProjectionException.ValueNotFound(attribute.Metadata);
}
string variableName = attribute.Context.Lookup.Variable(attribute.Identity, attribute.Data.Input);
string dialectName = attribute.Context.Domain.Dialect.Variable(variableName);
return(attribute.Append(dialectName));
}
/// <summary>
/// Appends the current variable name, e.g. <c>@V0</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 Var(this IProjectionAttribute attribute)
{
if (attribute.Field == null)
{
throw ProjectionException.ValueNotFound(attribute);
}
IField field = ProjectionHelper.GetFieldValue(attribute);
string variableName = attribute.Context.Lookup.Variable(attribute.Identity, field);
string dialectName = attribute.Context.Domain.Dialect.Variable(variableName);
return(attribute.Append(dialectName));
}
public static IProjection Val(this IProjection projection)
{
if (projection.Data == null)
{
throw ProjectionException.ValueNotFound(projection.Metadata);
}
IProjectionData newData = ProjectionData.Resolve(projection.Data, projection.Metadata);
if (newData.Source.Snapshot == null)
{
throw ProjectionException.ValueNotFound(newData.Source);
}
return(projection.With(data: newData));
}
/// <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 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 IProjectionAttribute ValList(this IProjection projection, Func <IProjectionAttribute, IProjectionAttribute> itemFactory)
{
if (projection.Source == null)
{
throw ProjectionException.ValueNotFound(projection);
}
IField[] items = new Relation(projection.Source, projection.Metadata.Identity.Name).Column().ToArray();
IProjectionAttribute attribute = projection.Attr();
if (items.Length == 0)
{
return(attribute);
}
attribute = itemFactory(attribute.With(metadata: attribute.Metadata, field: () => items[0]));
foreach (IField item in items.Skip(1))
{
attribute = itemFactory(attribute.With(field: () => item).Append(", "));
}
return(attribute);
}