====== Data Resource - Target Data URI ======

===== About =====
A ''target uri'' is a ''uri'' that defines one or more [[docs:flow:target|target resources]] for [[docs:op:transfer|data transfer operations]].


===== Example =====
==== Reusing the name of the source in the target ====

The below target data uri
<code>
new_$name@sqlite
</code>
will define the ''target resource''
  * located in the sqlite connection
  * and a name that is composed of
    * the prefix ''new_''
    * and the [[docs:resource:name|name of the data source]] (''$name'')

Example: if the source table name is ''time'', the target table name would be ''new_time''

==== Using a part of source name in the target ====

With a [[docs:common:globbing|glob pattern]], you can reference parts of the source.

Example with the below [[data_selector|data selector]]
<code>
D?*@sqlite
</code>
and the below target data uri
<code>
$2@sqlite
</code>
  * if the source table name were ''D_TIME'', ''D_CUSTOMERS'',
  * the target table names would be ''TIME'', ''CUSTOMERS''

==== File system ====

In a shell such as powsershell, the ''$'' character should be quoted. (That's why [[docs:common:bash|we recommand bash]])

<code bash>
tabli data copy '*/bootstrap.min.css@cd' '/boot/bootstrap.$1.min.css@cd'
</code>


===== Syntax =====


<code bash>
pattern[@connection]
</code>
where:
  * ''connection'' is the [[docs:connection:name|name of a connection]]
  * ''pattern'' is an expression that define the name of the target. This pattern can include the captured characters from the [[data_selector|data selector]] glob expression.

==== Glob Backreference ====


In the pattern, you can reference a [[docs:common:globbing|globbing matched wildcard]] from a [[data_selector|data source selector]] using the ''$x'' syntax where x indicates the index of a glob pattern. ie
      * ''$0'' defines the whole expression (ie the whole path)
      * ''$1'' defines the first matched wildcard
      * ''$2'' defines the second matched wildcard
      * and so on until ''$9''.


You can see the value of the back reference with the [[docs:tabli:data:list|tabli data list command]].
If you want to know the value of ''$1'', just ask for the attribute ''1''

Example with [[docs:system:tpcds|tpcds]] where we want to capture the name of the web table but without the prefix.
<unit>
<code bash>
tabli data list  -a name -a 1 web_*@tpcds
</code>
<console>

name          1         
-----------   -------   
web_page      page      
web_returns   returns   
web_sales     sales     
web_site      site

</console>
</unit>
==== Attribute Reference ====


In the pattern, you can reference a [[docs:resource:attribute|resource attribute]] using the ''$x'' or ''${x}'' syntax where x indicates the name of the attribute.

Example:
      * ''$logicalName'' defines the [[docs:resource:logicalname|logical name]] of the resource

You can see all available attributes with the [[docs:tabli:data:info|data info command]].

<unit>
<code bash>
tabli data info web_page@tpcds
</code>
<console>
Information about the data resource (web_page@tpcds)
attribute         value                                                                                              
---------------   ------------------------------------------------------------------------------------------------   
AbsolutePath      web_page                                                                                           
Connection        tpcds                                                                                              
DataUri           web_page@tpcds                                                                                     
LogicalName       web_page                                                                                           
Md5               2d3f08a0ad007e5236ed694250e89721                                                                   
Name              web_page                                                                                           
Parent            /                                                                                                  
Path              web_page                                                                                           
Sha384            0d3fcd0bd2dc1aa6c14a6ce4a4c8acff06a6194a4f56f4730bbb371aaf490da1fe318f9f11ba44157ffd53d501e2f551   
Sha384Integrity   sha384-DT/NC9LcGqbBSmzkpMis/wamGUpPVvRzC7s3Gq9JDaH+MY+fEbpEFX/9U9UB4vVR                            
SubType           table                                                                                              
Type              table
</console>
</unit>

==== Column Value Reference ====

If your step is running on [[docs:flow:granularity|record level]], you can also add a column value using the ''$x'' or ''${x}'' syntax where x indicate the [[docs:resource:column|column name]].