Functions - Utilities
=====================
The following utility functions are supported: 

`COMPUTE_HASH_CODE`_, 
`COMPUTE_HASH_CODE_STR`_,
`GETHOSTNAME`_,
`GETUSER`_,
`GET_AUTHENTICATED_USERNAME`_,
`GET_CPU_ID`_, 
`GET_ONETICK_RELEASE`_, 
`GET_ONETICK_VERSION`_, 
`GET_SERVER_PORT`_, 
`GET_THREAD_ID`_, 
`GET_THREAD_NAME`_, 
`GET_TOP_LEVEL_QUERY_ID`_,
`GET_TOP_LEVEL_QUERY_NAME`_, 
`GET_TYPE`_, 
`GET_USER_ROLES`_,
`SELECT_MATCHING_FIELDS`_,
`UNDEFINED`_,
`UUID`_.


COMPUTE_HASH_CODE
#################

Returns the long hash code for the specified string with the hash function provided by the hash_function parameter. 
Possible values of the hash_function are ``DEFAULT``, ``SUM_OF_BYTES``, ``LOOKUP3``, ``METRO_HASH_64``, ``CITY_HASH_64`` and ``MURMUR_HASH_64``. 
Default value of hash_function is ``DEFAULT``.

| Simple Syntax: 
| ``long COMPUTE_HASH_CODE(string str [, string hash_function])``

.. code-block:: sql
   :caption: COMPUTE_HASH_CODE Function Example

   select PRICE, SIZE, EXCHANGE,
   -- Hash functions include:  DEFAULT, SUM_OF_BYTES, LOOKUP3, METRO_HASH_64, CITY_HASH_64 and MURMUR_HASH_64
   COMPUTE_HASH_CODE(EXCHANGE,'DEFAULT') as N_COMPUTE_HASH_CODE	
   from US_COMP_SAMPLE.TRD                  
   where SYMBOL_NAME='CSCO'                    
   and TIMESTAMP >= '2024-01-03 00:00:00 UTC'  
   and TIMESTAMP < '2024-01-04 00:00:00 UTC'   
   limit 10

.. csv-table:: COMPUTE_HASH_CODE Function Example Results
   :header: ,Timestamp,PRICE,SIZE,EXCHANGE,N_COMPUTE_HASH_CODE

   0,2024-01-03 00:00:40.413537416,50.56,17,Q,81
   1,2024-01-03 00:00:40.413540299,50.57,33,Q,81
   2,2024-01-03 00:03:34.026455739,50.52,26,P,80
   3,2024-01-03 00:03:34.026458843,50.51,123,P,80
   4,2024-01-03 00:03:34.026459421,50.49,3,P,80
   5,2024-01-03 00:05:06.042217019,50.4896,1,D,68
   6,2024-01-03 00:07:11.737983252,50.4897,1,D,68
   7,2024-01-03 00:12:17.787582635,50.49,1,D,68
   8,2024-01-03 00:13:16.630750984,50.49,3,P,80
   9,2024-01-03 00:14:14.187418230,50.49,100,P,80



COMPUTE_HASH_CODE_STR
#####################

Returns as a string the hexadecimal encoded hash code for the specified string with the hash function provided by the hash_function parameter. 
Possible values of the hash_function are ``DEFAULT``, ``SUM_OF_BYTES``, ``LOOKUP3``, ``METRO_HASH_64``, ``CITY_HASH_64``, ``MURMUR_HASH_64``, ``SHA_1``, ``SHA_224``, ``SHA_256``, ``SHA_384``, ``SHA_512``. 
Default value of hash_function is ``DEFAULT``.
Note that trailing nulls also will be hashed in case of fixed size strings.

| Simple Syntax: 
| ``string COMPUTE_HASH_CODE_STR(string str [, string hash_function])``

.. code-block:: sql
   :caption: COMPUTE_HASH_CODE_STR Function Example

   select PRICE, SIZE, EXCHANGE, 
   COMPUTE_HASH_CODE_STR(EXCHANGE,'DEFAULT') as S_COMPUTE_HASH_CODE_STR
   from US_COMP_SAMPLE.TRD                  
   where SYMBOL_NAME='CSCO'                    
   and TIMESTAMP >= '2024-01-03 00:00:00 UTC'  
   and TIMESTAMP < '2024-01-04 00:00:00 UTC'   
   limit 10

.. csv-table:: COMPUTE_HASH_CODE_STR Function Example Results
   :header: ,Timestamp,PRICE,SIZE,EXCHANGE,S_COMPUTE_HASH_CODE_STR

   0,2024-01-03 00:00:40.413537416,50.56,17,Q,5100000000000000
   1,2024-01-03 00:00:40.413540299,50.57,33,Q,5100000000000000
   2,2024-01-03 00:03:34.026455739,50.52,26,P,5000000000000000
   3,2024-01-03 00:03:34.026458843,50.51,123,P,5000000000000000
   4,2024-01-03 00:03:34.026459421,50.49,3,P,5000000000000000
   5,2024-01-03 00:05:06.042217019,50.4896,1,D,4400000000000000
   6,2024-01-03 00:07:11.737983252,50.4897,1,D,4400000000000000
   7,2024-01-03 00:12:17.787582635,50.49,1,D,4400000000000000
   8,2024-01-03 00:13:16.630750984,50.49,3,P,5000000000000000
   9,2024-01-03 00:14:14.187418230,50.49,100,P,5000000000000000


GETHOSTNAME
###########

Returns the name of the host where this function runs.

| Simple Syntax: 
| ``string GETHOSTNAME()``

.. code-block:: sql
   :caption: GETHOSTNAME Function Example

   select GETHOSTNAME() as S_GETHOSTNAME
   from US_COMP_SAMPLE.TRD                  
   where SYMBOL_NAME='CSCO'                    
   and TIMESTAMP >= '2024-01-03 00:00:00 UTC'  
   and TIMESTAMP < '2024-01-04 00:00:00 UTC'   
   limit 1

.. csv-table:: GETHOSTNAME Function Example Results
   :header: ,Timestamp,S_GETHOSTNAME

   0,2024-01-03 00:00:40.413537416,50.56,17,ip-10-36-13-161.ec2.internal



GETUSER
#######

Returns the name of the user who is executing the query.

| Simple Syntax: 
| ``string string GETUSER()``

.. code-block:: sql
   :caption: GETUSER Function Example

   select GETUSER() as S_GETUSER
   from US_COMP_SAMPLE.TRD                  
   where SYMBOL_NAME='CSCO'                    
   and TIMESTAMP >= '2024-01-03 00:00:00 UTC'  
   and TIMESTAMP < '2024-01-04 00:00:00 UTC'   
   limit 1

.. csv-table:: GETUSER Function Example Results
   :header: ,Timestamp,S_GETUSER

   0,2024-01-03 00:00:40.413537416,ccf_omd_ps_app_1



GET_AUTHENTICATED_USERNAME
##########################

Returns the authenticated login name of the user who is executing the query.

| Simple Syntax: 
| ``string string GET_AUTHENTICATED_USERNAME()``

.. code-block:: sql
   :caption: GET_AUTHENTICATED_USERNAME Function Example

   select GET_AUTHENTICATED_USERNAME() as S_GET_AUTHENTICATED_USERNAME
   from US_COMP_SAMPLE.TRD                  
   where SYMBOL_NAME='CSCO'                    
   and TIMESTAMP >= '2024-01-03 00:00:00 UTC'  
   and TIMESTAMP < '2024-01-04 00:00:00 UTC'   
   limit 1

.. csv-table:: GET_AUTHENTICATED_USERNAME Function Example Results
   :header: ,Timestamp,S_GET_AUTHENTICATED_USERNAME

   0,2024-01-03 00:00:40.413537416,ccf_omd_ps_app_1


GET_CPU_ID
##########

Returns the ID of the CPU core that is executing this function.

| Simple Syntax: 
| ``int GET_CPU_ID()``

.. code-block:: sql
   :caption: GET_CPU_ID Function Example

   select GET_CPU_ID() as N_GET_CPU_ID
   from US_COMP_SAMPLE.TRD                  
   where SYMBOL_NAME='CSCO'                    
   and TIMESTAMP >= '2024-01-03 00:00:00 UTC'  
   and TIMESTAMP < '2024-01-04 00:00:00 UTC'   
   limit 1

.. csv-table:: GET_CPU_ID Function Example Results
   :header: ,Timestamp,N_GET_CPU_ID

   0,2024-01-03 00:00:40.413537416,11


GET_ONETICK_RELEASE
###################

Returns the build name of OneTick, for example, BUILD_rel_20250227_initial.

| Simple Syntax: 
| ``string GET_ONETICK_RELEASE()``

.. code-block:: sql
   :caption: GET_ONETICK_RELEASE Function Example

   select GET_ONETICK_RELEASE() as S_GET_ONETICK_RELEASE
   from US_COMP_SAMPLE.TRD                  
   where SYMBOL_NAME='CSCO'                    
   and TIMESTAMP >= '2024-01-03 00:00:00 UTC'  
   and TIMESTAMP < '2024-01-04 00:00:00 UTC'   
   limit 1

.. csv-table:: GET_ONETICK_RELEASE Function Example Results
   :header: ,Timestamp,S_GET_ONETICK_RELEASE

   0,2024-01-03 00:00:40.413537416,BUILD_rel_20250227_update4


GET_ONETICK_VERSION
###################

Returns the OneTick version (build number) represented as YYYYMMDDHHmmSS.

| Simple Syntax: 
| ``long GET_ONETICK_VERSION()``

.. code-block:: sql
   :caption: GET_ONETICK_VERSION Function Example

   select GET_ONETICK_VERSION() as N_GET_ONETICK_VERSION
   from US_COMP_SAMPLE.TRD                  
   where SYMBOL_NAME='CSCO'                    
   and TIMESTAMP >= '2024-01-03 00:00:00 UTC'  
   and TIMESTAMP < '2024-01-04 00:00:00 UTC'   
   limit 1

.. csv-table:: GET_ONETICK_VERSION Function Example Results
   :header: ,Timestamp,N_GET_ONETICK_VERSION

   0,2024-01-03 00:00:40.413537416,20250227120000



GET_SERVER_PORT
###############

Returns the port number of the  server, where this function is executing. 

| Simple Syntax: 
| ``int GET_SERVER_PORT()``

.. code-block:: sql
   :caption: GET_SERVER_PORT Function Example

   select GET_SERVER_PORT() as N_GET_SERVER_PORT
   from US_COMP_SAMPLE.TRD                  
   where SYMBOL_NAME='CSCO'                    
   and TIMESTAMP >= '2024-01-03 00:00:00 UTC'  
   and TIMESTAMP < '2024-01-04 00:00:00 UTC'   
   limit 1

.. csv-table:: GET_SERVER_PORT Function Example Results
   :header: ,Timestamp,N_GET_SERVER_PORT

   0,2024-01-03 00:00:40.413537416,40001




GET_THREAD_ID
#############

Returns the ID of the thread that is executing this function.

| Simple Syntax: 
| ``int GET_THREAD_ID()``

.. code-block:: sql
   :caption: GET_THREAD_ID Function Example

   select GET_THREAD_ID() as N_GET_THREAD_ID
   from US_COMP_SAMPLE.TRD                  
   where SYMBOL_NAME='CSCO'                    
   and TIMESTAMP >= '2024-01-03 00:00:00 UTC'  
   and TIMESTAMP < '2024-01-04 00:00:00 UTC'   
   limit 1

.. csv-table:: GET_THREAD_ID Function Example Results
   :header: ,Timestamp,N_GET_THREAD_ID

   0,2024-01-03 00:00:40.413537416,139894414652992



GET_THREAD_NAME
###############

Returns the name of the thread that is executing this function.

| Simple Syntax: 
| ``string GET_THREAD_NAME()``

.. code-block:: sql
   :caption: GET_THREAD_NAME Function Example

   select GET_THREAD_NAME() as S_GET_THREAD_NAME
   from US_COMP_SAMPLE.TRD                  
   where SYMBOL_NAME='CSCO'                    
   and TIMESTAMP >= '2024-01-03 00:00:00 UTC'  
   and TIMESTAMP < '2024-01-04 00:00:00 UTC'   
   limit 1

.. csv-table:: GET_THREAD_NAME Function Example Results
   :header: ,Timestamp,S_GET_THREAD_NAME

   0,2024-01-03 00:00:40.413537416,OMD_PS.785


GET_TOP_LEVEL_QUERY_ID
######################

Returns the unique ID of this query.

| Simple Syntax: 
| ``string GET_TOP_LEVEL_QUERY_ID()``

.. code-block:: sql
   :caption: GET_TOP_LEVEL_QUERY_ID Function Example

   select GET_TOP_LEVEL_QUERY_ID() as S_GET_TOP_LEVEL_QUERY_ID
   from US_COMP_SAMPLE.TRD                  
   where SYMBOL_NAME='CSCO'                    
   and TIMESTAMP >= '2024-01-03 00:00:00 UTC'  
   and TIMESTAMP < '2024-01-04 00:00:00 UTC'   
   limit 1

.. csv-table:: GET_TOP_LEVEL_QUERY_ID Function Example Results
   :header: ,Timestamp,S_GET_TOP_LEVEL_QUERY_ID

   0,2024-01-03 00:00:40.413537416,ip-10-36-13-227.96777.20250416093102.899.21221


GET_TOP_LEVEL_QUERY_NAME
########################

Returns the unique ID of this query.

| Simple Syntax: 
| ``string GET_TOP_LEVEL_QUERY_NAME()``

.. code-block:: sql
   :caption: GET_TOP_LEVEL_QUERY_NAME Function Example

   select GET_TOP_LEVEL_QUERY_NAME() as S_GET_TOP_LEVEL_QUERY_NAME
   from US_COMP_SAMPLE.TRD                  
   where SYMBOL_NAME='CSCO'                    
   and TIMESTAMP >= '2024-01-03 00:00:00 UTC'  
   and TIMESTAMP < '2024-01-04 00:00:00 UTC'   
   limit 1

.. csv-table:: GET_TOP_LEVEL_QUERY_NAME Function Example Results
   :header: ,Timestamp,S_GET_TOP_LEVEL_QUERY_NAME

   0,2024-01-03 00:00:40.413537416,File1


GET_TYPE
######## 

Returns the type name of the field name.  Possible return values are byte, string, short, int, float, uint, long, double, msectime, and nsectime.

| Simple Syntax: 
| ``string GET_TYPE(field_name)``

.. code-block:: sql
   :caption: GET_TYPE Function Example

   select PRICE, GET_TYPE(PRICE) as S_GET_TYPE
   from US_COMP_SAMPLE.TRD                  
   where SYMBOL_NAME='CSCO'                    
   and TIMESTAMP >= '2024-01-03 00:00:00 UTC'  
   and TIMESTAMP < '2024-01-04 00:00:00 UTC'   
   limit 1

.. csv-table:: GET_TYPE Function Example Results
   :header: ,Timestamp,PRICE,S_GET_TYPE

   0,2024-01-03 00:00:40.413537416,50.56,double


GET_USER_ROLES
##############

Returns a comma-separated list of the roles of the user who is executing the query.

| Simple Syntax: 
| ``string GET_USER_ROLES()``

.. code-block:: sql
   :caption: GET_USER_ROLES Function Example

   select GET_USER_ROLES() as S_GET_USER_ROLES
   from US_COMP_SAMPLE.TRD                  
   where SYMBOL_NAME='CSCO'                    
   and TIMESTAMP >= '2024-01-03 00:00:00 UTC'  
   and TIMESTAMP < '2024-01-04 00:00:00 UTC'   
   limit 1

.. csv-table:: GET_TOP_LEVEL_QUERY_NAME Function Example Results
   :header: ,Timestamp,S_GET_USER_ROLES

   0,2024-01-03 00:00:40.413537416,OMD_PS


SELECT_MATCHING_FIELDS
######################

Returns a comma-separated list of schema field names filtered by name (the ``regex`` parameter) and optionally by type (the ``field_types`` parameter). 
A field is included in the resulting comma-separated field list if its name in the schema fully matches the regex parameter.
If field_types parameter is specified, then the type of the field is among those listed in the field_types parameter.

regex - A regular expression to match field names with.

The following field  types are supported: ``byte``, ``string``, ``varstring``, ``short``, ``int``, ``uint``, ``float``, ``timeoffset``, ``long``, ``ulong``, ``double``, ``msectime``, ``nsectime``, ``decimal128``. 

| Simple Syntax: 
| ``string SELECT_MATCHING_FIELDS(string regex[, string field_types])``

.. code-block:: sql
   :caption: SELECT_MATCHING_FIELDS Function Example

   select SELECT_MATCHING_FIELDS('.*PRICE','double') as S_SELECT_MATCHING_FIELDS
   from US_COMP_SAMPLE.QTE                  
   where SYMBOL_NAME='CSCO'                    
   and TIMESTAMP >= '2024-01-03 00:00:00 UTC'  
   and TIMESTAMP < '2024-01-04 00:00:00 UTC'   
   limit 1

.. csv-table:: SELECT_MATCHING_FIELDS Function Example Results
   :header: ,Timestamp,S_SELECT_MATCHING_FIELDS

   0,2024-01-03 00:00:40.413537416,BID_PRICE



UNDEFINED
#########

Returns false if a field with a given name was declared, and true otherwise. The parameter name is a string and must be quoted.

| Simple Syntax: 
| ``bool UNDEFINED(string name)``

.. code-block:: sql
   :caption: UNDEFINED Function Example

   select PRICE,
   UNDEFINED('PRICE')  as N_UNDEFINED,
   UNDEFINED('PRICE_D')  as N_UNDEFINED2
   from US_COMP_SAMPLE.TRD                  
   where SYMBOL_NAME='CSCO'                    
   and TIMESTAMP >= '2024-01-03 00:00:00 UTC'  
   and TIMESTAMP < '2024-01-04 00:00:00 UTC'   
   limit 1

.. csv-table:: UNDEFINED Function Example Results
   :header: ,Timestamp,PRICE,N_UNDEFINED,N_UNDEFINED2

   0,2024-01-03 00:00:40.413537416,50.56,0.0,1.0

   0,2024-01-03 00:00:40.413537416,OMD_PS


UUID
####

Returns a unique identifier in form: [mac_address].[timestamp].[process_id].[seq_num], where:

- ``mac_address`` - is the mac address of the machine
- ``timestamp`` - the current time expressed as the number of milliseconds since the UNIX epoch
- ``process_id`` - process ID
- ``seq_num`` - is a unique to a process integer that is incremented per call to this function


| Simple Syntax: 
| ``string UUID()``

.. code-block:: sql
   :caption: UUID Function Example

   select UUID() as S_UUID
   from US_COMP_SAMPLE.TRD                  
   where SYMBOL_NAME='CSCO'                    
   and TIMESTAMP >= '2024-01-03 00:00:00 UTC'  
   and TIMESTAMP < '2024-01-04 00:00:00 UTC'   
   limit 1

.. csv-table:: UUID Function Example Results
   :header: ,Timestamp,S_UUID

   0,2024-01-03 00:00:40.413537416,12F0E7B3CE6B.1744796538466.344146.1



   0,2024-01-03 00:00:40.413537416,OMD_PS