public static class ColumnFilter.Builder
extends java.lang.Object
ColumnFilter
object.
Note that the columns added to this build are the _queried_ column. Whether or not all columns
are _fetched_ depends on which constructor you've used to obtained this builder, allRegularColumnsBuilder (all
columns are fetched) or selectionBuilder (only the queried columns are fetched).
Note that for a allRegularColumnsBuilder, if no queried columns are added, this is interpreted as querying
all columns, not querying none (but if you know you want to query all columns, prefer
ColumnFilter.all(TableMetadata)
. For selectionBuilder, adding no queried columns means no column will be
fetched (so the builder will return PartitionColumns.NONE
).
Also, if only a sub-selection of a complex column should be queried, then only the corresponding
sub-selection method of the builder (slice(org.apache.cassandra.schema.ColumnMetadata, org.apache.cassandra.db.rows.CellPath, org.apache.cassandra.db.rows.CellPath)
or select(org.apache.cassandra.schema.ColumnMetadata, org.apache.cassandra.db.rows.CellPath)
) should be called for the
column, but add(org.apache.cassandra.schema.ColumnMetadata)
shouldn't. if add(org.apache.cassandra.schema.ColumnMetadata)
is also called, the whole column will be
queried and the sub-selection(s) will be ignored. This is done for correctness of CQL where
if you do "SELECT m, m[2..5]", you are really querying the whole collection.Modifier and Type | Method and Description |
---|---|
ColumnFilter.Builder |
add(ColumnMetadata c) |
ColumnFilter.Builder |
addAll(java.lang.Iterable<ColumnMetadata> columns) |
ColumnFilter |
build() |
ColumnFilter.Builder |
select(ColumnMetadata c,
CellPath elt) |
ColumnFilter.Builder |
slice(ColumnMetadata c,
CellPath from,
CellPath to) |
public ColumnFilter.Builder add(ColumnMetadata c)
public ColumnFilter.Builder addAll(java.lang.Iterable<ColumnMetadata> columns)
public ColumnFilter.Builder slice(ColumnMetadata c, CellPath from, CellPath to)
public ColumnFilter.Builder select(ColumnMetadata c, CellPath elt)
public ColumnFilter build()
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