feat: add SQL syntax support for alter, execute, describe, show, drop task

[ZhiHanZ]

… task

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Summary

1. Support Alter Task Semantics

2. Support Drop Task Semantics

3. Support Execute Task Semantics

4. Support Describe Task Semantics

5. Support Show Task Semantics

6. Add Unit Tests

Description

Alter Task Semantics

ALTER TASK [ IF EXISTS ] <name> RESUME | SUSPEND

ALTER TASK [ IF EXISTS ] <name> MODIFY AS <sql>

ALTER TASK [ IF EXISTS ] <name> SET
  [ WAREHOUSE = <string> ]
  [ SCHEDULE = '{ <number> MINUTE | USING CRON <expr> <time_zone> }' ]
  [ SUSPEND_TASK_AFTER_NUM_FAILURES = <num> ]
  [ COMMENT = <string> ]

ALTER TASK [ IF EXISTS ] <name> UNSET
  [ WAREHOUSE ]

Parameter	Description
<name>	The name of the task to be altered.
RESUME | SUSPEND	These keywords are used to either resume or suspend the specified task.
MODIFY AS <sql>	Modifies the SQL statement of the specified task to the new SQL statement provided.
SET	This keyword is followed by one or more of the optional settings below, to modify the configuration of the specified task.
- WAREHOUSE = <string>	Sets the warehouse for the specified task to the provided string value.
- SCHEDULE = '{ <number> MINUTE | USING CRON <expr> <time_zone> }'	Sets the schedule for the specified task. You can specify an interval in minutes or a cron expression along with a timezone.
- SUSPEND_TASK_AFTER_NUM_FAILURES = <num>	Sets the number of consecutive failures after which the task should be suspended, to the provided numeric value.
- COMMENT = <string>	Sets the comment or description for the specified task to the provided string value. This is useful for documenting the purpose or behavior of the task.
UNSET	This keyword is followed by one or more of the optional settings below, to remove the specified configurations from the task.
- [ WAREHOUSE ]	Unsets the warehouse setting for the specified task, reverting it to the default or previous setting.

Examples

Certainly! Below are descriptions for the provided SQL commands in the expected format:

---

The following example resumes the task named MyTask1.

ALTER TASK MyTask1 RESUME

---

The following example suspends the task named MyTask1.

ALTER TASK MyTask1 SUSPEND

---

The following example modifies the settings of the task named MyTask1, setting a specific warehouse, a cron schedule, and a comment.

ALTER TASK MyTask1 SET WAREHOUSE= 'MyWarehouse' SCHEDULE = USING CRON '0 6 * * *' 'America/Los_Angeles' COMMENT = 'serverless + cron'

---

The following example modifies the settings of the task named MyTask1, setting a specific warehouse, an interval schedule, the number of failures after which to suspend the task, and a comment.

ALTER TASK MyTask1 SET WAREHOUSE= 'MyWarehouse' SCHEDULE = 13 MINUTE SUSPEND_TASK_AFTER_NUM_FAILURES = 10 COMMENT = 'serverless + cron'

---

The following example modifies the SQL statement of the task named MyTask2 to a new SQL statement.

ALTER TASK MyTask2 MODIFY AS SELECT CURRENT_VERSION()

Drop Task Semantics

DROP TASK [ IF EXISTS ] <name>

Parameter	Description
[ IF EXISTS ]	This optional clause prevents an error from occurring if the task does not exist.
<name>	The name of the task to be dropped.

Examples

---

The following example drops the task named MyTask1 if it exists.

DROP TASK IF EXISTS MyTask1

---

Show Tasks Semantics

SHOW TASKS [ LIKE '<pattern>' ]

Parameter	Description
[ LIKE '<pattern>' ]	This optional clause filters the tasks to be shown based on a pattern matching the task names.

Examples

---

The following example shows all tasks with names that start with My.

SHOW TASKS LIKE 'My%'

---

Describe Task Semantics

DESC | DESCRIBE TASK <name>

Parameter	Description
<name>	The name of the task to be described.

Examples

---

The following example describes the task named MyTask1.

DESC TASK MyTask1

---

Execute Task Semantics

EXECUTE TASK <name>

Parameter	Description
<name>	The name of the task to be executed.

Examples

---

The following example executes the task named MyTask1.

EXECUTE TASK MyTask1

---

• It could be viewed as a succession of feat: impl create task sql parser and planner #13316 and finish the basic task semantics

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