com.datastax.driver.core.querybuilder

Class Select.SelectionOrAlias

java.lang.Object

com.datastax.driver.core.querybuilder.Select.Builder

com.datastax.driver.core.querybuilder.Select.Selection

com.datastax.driver.core.querybuilder.Select.SelectionOrAlias

Enclosing class:

Select

public static class Select.SelectionOrAlias
extends Select.Selection

An Selection clause for an in-construction SELECT statement.

This only differs from Select.Selection in that you can add an alias for the previously selected item through as(java.lang.String).

Constructor Summary

Constructors

Constructor and Description
SelectionOrAlias()

Method Summary

Modifier and Type	Method and Description
Select.Builder	all() Selects all columns (i.e.
Select.Selection	as(String alias) Adds an alias for the just selected item.
Select.SelectionOrAlias	cast(Object column, DataType targetType) Creates a cast of an expression to a given CQL type.
Select.SelectionOrAlias	column(String name) Selects the provided column.
Select.Builder	countAll() Selects the count of all returned rows (i.e.
Select.SelectionOrAlias	fcall(String name, Object... parameters) Creates a function call.
Select	from(String keyspace, String table) Adds the table to select from.
Select	from(TableMetadata table) Adds the table to select from.
Select.SelectionOrAlias	path(String... segments) Selects the provided path.
Select.SelectionOrAlias	raw(String rawString) Selects the provided raw expression.
Select.SelectionOrAlias	toJson(String name) Creates a toJson() function call.
Select.SelectionOrAlias	ttl(String name) Selects the ttl of provided column.
Select.SelectionOrAlias	writeTime(String name) Selects the write time of provided column.

Methods inherited from class com.datastax.driver.core.querybuilder.Select.Selection

distinct, json

Methods inherited from class com.datastax.driver.core.querybuilder.Select.Builder

from

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

SelectionOrAlias

public SelectionOrAlias()

Method Detail

as

public Select.Selection as(String alias)

Adds an alias for the just selected item.

Parameters:

alias - the name of the alias to use.

Returns:

this in-build SELECT statement

all

public Select.Builder all()

Description copied from class: Select.Selection

Selects all columns (i.e. "SELECT * ...")

Specified by:

all in class Select.Selection

Returns:

an in-build SELECT statement.

countAll

public Select.Builder countAll()

Description copied from class: Select.Selection

Selects the count of all returned rows (i.e. "SELECT count(*) ...").

Specified by:

countAll in class Select.Selection

Returns:

an in-build SELECT statement.

column

public Select.SelectionOrAlias column(String name)

Description copied from class: Select.Selection

Selects the provided column.

Specified by:

column in class Select.Selection

Parameters:

name - the new column name to add.

Returns:

this in-build SELECT statement

writeTime

public Select.SelectionOrAlias writeTime(String name)

Description copied from class: Select.Selection

Selects the write time of provided column.

This is a shortcut for fcall("writetime", QueryBuilder.column(name)).

Specified by:

writeTime in class Select.Selection

Parameters:

name - the name of the column to select the write time of.

Returns:

this in-build SELECT statement

ttl

public Select.SelectionOrAlias ttl(String name)

Description copied from class: Select.Selection

Selects the ttl of provided column.

This is a shortcut for fcall("ttl", QueryBuilder.column(name)).

Specified by:

ttl in class Select.Selection

Parameters:

name - the name of the column to select the ttl of.

Returns:

this in-build SELECT statement

fcall

public Select.SelectionOrAlias fcall(String name,
                                     Object... parameters)

Description copied from class: Select.Selection

Creates a function call.

Please note that the parameters are interpreted as values, and so fcall("textToBlob", "foo") will generate the string "textToBlob('foo')". If you want to generate "textToBlob(foo)", i.e. if the argument must be interpreted as a column name (in a select clause), you will need to use the QueryBuilder.column(java.lang.String) method, and so fcall("textToBlob", QueryBuilder.column(foo).

Specified by:

fcall in class Select.Selection

Parameters:

name - the name of the function.

parameters - the parameters for the function call.

Returns:

this in-build SELECT statement

cast

public Select.SelectionOrAlias cast(Object column,
                                    DataType targetType)

Description copied from class: Select.Selection

Creates a cast of an expression to a given CQL type.

Overrides:

cast in class Select.Selection

Parameters:

column - the expression to cast. It can be a complex expression like a function call.

targetType - the target CQL type to cast to. Use static methods such as DataType.text().

Returns:

this in-build SELECT statement.

raw

public Select.SelectionOrAlias raw(String rawString)

Description copied from class: Select.Selection

Selects the provided raw expression.

The provided string will be appended to the query as-is, without any form of escaping or quoting.

Overrides:

raw in class Select.Selection

Parameters:

rawString - the raw expression to add.

Returns:

this in-build SELECT statement

path

public Select.SelectionOrAlias path(String... segments)

Description copied from class: Select.Selection

Selects the provided path.

All given path segments will be concatenated together with dots. If any segment contains an identifier that needs quoting, caller code is expected to call QueryBuilder.quote(String) prior to invoking this method.

This method is currently only useful when accessing individual fields of a user-defined type (UDT), which is only possible since CASSANDRA-7423.

Note that currently nested UDT fields are not supported and will be rejected by the server as a syntax error.

Overrides:

path in class Select.Selection

Parameters:

segments - the segments of the path to create.

Returns:

this in-build SELECT statement

See Also:

CASSANDRA-7423

toJson

public Select.SelectionOrAlias toJson(String name)

Description copied from class: Select.Selection

Creates a toJson() function call. This is a shortcut for fcall("toJson", QueryBuilder.column(name)).

Support for JSON functions has been added in Cassandra 2.2. The toJson() function is similar to SELECT JSON statements, but applies to a single column value instead of the entire row, and produces a JSON-encoded string representing the normal Cassandra column value.

It may only be used in the selection clause of a SELECT statement.

Overrides:

toJson in class Select.Selection

Returns:

the function call.

See Also:

JSON Support for CQL, JSON Support in Cassandra 2.2

from

public Select from(String keyspace,
                   String table)

Description copied from class: Select.Builder

Adds the table to select from.

Overrides:

from in class Select.Builder

Parameters:

keyspace - the name of the keyspace to select from.

table - the name of the table to select from.

Returns:

a newly built SELECT statement that selects from keyspace.table.

from

public Select from(TableMetadata table)

Description copied from class: Select.Builder

Adds the table to select from.

Overrides:

from in class Select.Builder

Parameters:

table - the table to select from.

Returns:

a newly built SELECT statement that selects from table.