The ph_task Table

The ph_task table contains information about Scheduler tasks and sensors. The ph_task table contains built-in tasks and sensors that are scheduled to run automatically.

Table 1. The ph_task table
Column	Type	Description
tk_id	serial	Sequential job ID. System updated; do not modify. Referenced in the alert_task_id column in the ph_alert table and in the run_task_id column in the ph_run table.
tk_name	char(36)	Job name. A unique index on this column ensures that no two names are the same. Referenced in the task_name column of the ph_threshold table.
tk_description	lvarchar	Description about what the task or sensor does.
tk_type	char(18)	Type of job: TASK: Invokes an action at a specific time and frequency SENSOR: (Default) A task that collects, stores, and purges data to or from a result table STARTUP TASK: A task that runs only when the server starts STARTUP SENSOR: A sensor that runs only when the server starts
tk_sequence	integer	Current® data collection number. System updated; do not modify. Referenced in the alert_task_id column of the ph_alert table and the run_task_seq column of the ph_run table.
tk_result_table	varchar	Results table name for storing data collected by a sensor. The table is created by the CREATE TABLE statement in the tk_create column.
tk_create	lvarchar	The CREATE TABLE statement used to create the results table to store data collected by a sensor. One of the columns in the table must be named ID and hold the tk_sequence value. This value indicates the age of the row and can be used for purging the row.
tk_dbs	varchar(250)	The database in which the task is run. Default is `sysadmin`.
tk_execute	lvarchar	The SQL statement to execute. The length of the command is limited to 2048 bytes.
tk_delete	interval day(2) to second	Data older than this interval is deleted from the result table. Default is `1:00:00` (one day).
tk_start_time	datetime hour to second	Time when the task or sensor starts. Default is `08:00:00`.
tk_stop_time	datetime hour to second	Time of day after which the task or sensor cannot be scheduled to be run. The database server schedules the next execution on the next valid day. Default is `19:00:00`. Can be `NULL`, indicating no stop time.
tk_frequency	interval day(2) to second	How often this task or sensor runs. Default is `1` (once a day).
tk_next_execution	datetime year to second	Next time this task or sensor will be run. After a startup task or sensor has run, this value is NULL. When a task or a sensor is enabled, the database server calculates this time from the values of tk_start_time, tk_stop_time, and tk_frequency columns, and the days of the week the task or sensor is enabled, according to the values of tk_monday, tk_tuesday, tk_wednesday, tk_thursday, tk_friday, tk_saturday, tk_sunday columns. For example, `new_next_execution_time = current_next_execution_time + tk_frequency`, where the `new_next_execution_time` is greater than the `current_next_execution_time`. If tk_frequency is not present, the task is run once.
tk_total_executions	integer	The number of times that the task or sensor was run. System updated; do not modify. Default is `0`.
tk_total_time	float	Total time spent executing this task or sensor. System updated; do not modify Default is `0.0` seconds.
tk_monday	boolean	Whether the task or sensor is run on Monday. Default is `T` (true).
tk_tuesday	boolean	Whether the task or sensor is run on Tuesday. Default is `T` (true).
tk_wednesday	boolean	Whether the task or sensor is run on Wednesday. Default is `T` (true).
tk_thursday	boolean	Whether the task or sensor is run on Thursday. Default is `T` (true).
tk_friday	boolean	Whether the task or sensor is run on Friday. Default is `T` (true).
tk_saturday	boolean	Whether the task or sensor is run on Saturday. Default is `T` (true).
tk_sunday	boolean	Whether the task or sensor is run on Sunday. Default is `T` (true).
tk_attributes	integer	Flags System updated; do not modify.
tk_group	varchar(128)	Group name. Must be the same as a value in the group_name column in the ph_group table. Default is `MISC`.
tk_enable	boolean	Whether the task or sensor is enabled. Default is `T` (the task is enabled).
tk_priority	integer	Job priority, on a scale of 0- 5, with higher numbers indicating higher priority. If there are several jobs to execute simultaneously, the job with the highest priority executes first. Default is `0` (low priority).