Class FromOptions

Namespace

NextORM.Core

Assembly

nextorm.core.dll

Per-query options for the primary FROM source, configured at query start through From<T>(IDataContext, Action<FromOptions>, Action<EntityMetadataBuilder<T>>?) (or the raw-table From(string, Action<FromOptions>) overload). The values are copied into the returned builder, so the options object is not retained.

public sealed class FromOptions

Inheritance

object

FromOptions

Inherited Members

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.ReferenceEquals(object, object)

object.ToString()

Extension Methods

ClickHouseEntityBuilderExtensions.Sample(FromOptions, double)

ClickHouseEntityBuilderExtensions.Sample(FromOptions, double, double)

EntityBuilderExtensions.AsEntityBuilder<T>(object?)

Methods

ForShare()

Locks the selected rows of this physical source in shared mode until the transaction ends, blocking while a locked row is held by another transaction. On PostgreSQL/MySQL it renders a targeted FOR SHARE OF <alias> clause; on SQL Server it applies the holdlock table hint to this source only. Requires a dialect whose lock renderer reports SupportsSourceLocks.

public FromOptions ForShare()

Returns

FromOptions

This instance, to allow chaining.

ForShare(LockWaitMode)

Locks the selected rows of this physical source in shared mode until the transaction ends, with the requested wait behaviour for rows already locked by another transaction. Requires a dialect whose lock renderer reports SupportsSourceLocks.

public FromOptions ForShare(LockWaitMode wait)

Parameters

wait LockWaitMode

How to react to a row already locked by another transaction.

Returns

FromOptions

This instance, to allow chaining.

ForUpdate()

Locks the selected rows of this physical source exclusively until the transaction ends, blocking while a locked row is held by another transaction. On PostgreSQL/MySQL it renders a targeted FOR UPDATE OF <alias> clause; on SQL Server it applies the updlock table hint to this source only. Requires a dialect whose lock renderer reports SupportsSourceLocks; a dialect without it (for example MariaDB) rejects the command with NotSupportedException. A whole-query ForUpdate() cannot be combined with a source lock.

public FromOptions ForUpdate()

Returns

FromOptions

This instance, to allow chaining.

ForUpdate(LockWaitMode)

Locks the selected rows of this physical source exclusively until the transaction ends, with the requested wait behaviour for rows already locked by another transaction. Requires a dialect whose lock renderer reports SupportsSourceLocks.

public FromOptions ForUpdate(LockWaitMode wait)

Parameters

wait LockWaitMode

How to react to a row already locked by another transaction.

Returns

FromOptions

This instance, to allow chaining.

TableSample(double, TableSampleMethod, double?)

Reads only percent percent of the primary table with a TABLESAMPLE modifier; seed makes the sample repeatable. Requires a dialect that supports it (see TableSample).

public FromOptions TableSample(double percent, TableSampleMethod method = TableSampleMethod.System, double? seed = null)

Parameters

percent double

The percentage of the table to sample; must be in (0, 100].

method TableSampleMethod

The sampling algorithm.

seed double?

An optional seed that makes the sample repeatable.

Returns

FromOptions

This instance, to allow chaining.

Exceptions

ArgumentOutOfRangeException

percent is not finite or is outside (0, 100].

WithIndex(IndexHintKind, params string[])

Attaches an index hint with an explicit kind to the primary physical table. With Ignore and no names, SQLite renders NOT INDEXED. Requires a dialect that supports index hints (see IndexHints). Null/blank names are ignored: a call with no usable name is a no-op unless kind is Ignore.

public FromOptions WithIndex(IndexHintKind kind, params string[] indexes)

Parameters

kind IndexHintKind

Whether to use, force or ignore the indexes.

indexes string[]

The index names to hint; may be empty for Ignore.

Returns

FromOptions

This instance, to allow chaining.

WithIndex(params string[])

Attaches an index hint to the primary physical table, asking the planner to consider indexes (USE INDEX on MySQL/MariaDB, INDEXED BY on SQLite, WITH (INDEX(...)) on SQL Server). Requires a dialect that supports index hints (see IndexHints); a dialect without a native form rejects the command with NotSupportedException. The names are emitted verbatim, so only use trusted values. Use the overload taking an NextORM.Core.FromOptions.IndexHintKind to force or ignore the indexes.

public FromOptions WithIndex(params string[] indexes)

Parameters

indexes string[]

The index names to hint; never empty.

Returns

FromOptions

This instance, to allow chaining.

WithSubQueryHint(string)

Attaches a provider-specific hint to a derived-table source (for example a PostgreSQL pg_hint_plan or MySQL optimizer hint), for example ctx.From(subquery, o => o.WithSubQueryHint("NestLoop(t1)")). Only a From(...) overload whose source is an explicit subquery can carry it; the SQL Server dialect rejects it because a query hint cannot be appended to a subselect.

public FromOptions WithSubQueryHint(string hint)

Parameters

hint string

The subquery hint text; must be non-empty.

Returns

FromOptions

This instance, to allow chaining.

Exceptions

ArgumentException

hint is null, empty or whitespace.

WithTableHint(params string[])

Attaches table-level hints to the primary physical table, for example ctx.From<IComplexEntity>(o => o.WithTableHint("nolock")) which renders from complex_entity with (nolock). Requires a dialect that supports table hints (see SupportsTableHints); the hints are rendered verbatim, so only use trusted values. Null/blank entries are ignored: a call that supplies no usable hint leaves the options unchanged.

public FromOptions WithTableHint(params string[] hints)

Parameters

hints string[]

The table hints to apply to the primary source (for example nolock).

Returns

FromOptions

This instance, to allow chaining.

WithoutIndex()

Tells the SQLite planner not to use any index (NOT INDEXED), or asks other dialects to ignore every named index. Requires a dialect that supports index hints (see IndexHints).

public FromOptions WithoutIndex()

Returns

FromOptions

This instance, to allow chaining.