CRM_Utils_SQL - Add "onDuplicate()" and "syncInto()" helpers

[totten]

Overview

This adds helper functions, onDuplicate(...) and syncInto(...), for reading data from one table and writing to another.

This is an offshoot of #17724 which only adds the helper function and the unit-test.

Before

It is possible to construct a SELECT query and insert the results to another table:

CRM_Utils_SQL_Select::from('foo_table')
  ->select(['foo_name', 'foo_value1', 'foo_value2'])
  ->insertInto('bar_table', ['bar_name', 'bar_output1', 'bar_output2']);

However, this will always insert new records. It cannot be used to UPDATE existing records (i.e. INSERT INTO ... SELECT ... ON DUPLICATE UPDATE...).

The operation REPLACE INTO (replaceInto()) is somewhat similar to ON DUPLICATE UPDATE. Both operations will insert a new record. But if there's a conflict/pre-existing record, the REPLACE INTO will remove and replace the record, whereas ON DUPLICATE UPDATE only modifies fields. One benchmark reported a ~35x performance difference between REPLACE INTO and ON DUPLICATE UPDATE.

After

This first commit makes it possible to construct an ON DUPLICATE UPDATE query, eg.

CRM_Utils_SQL_Select::from('foo_table')
  ->select(['foo_name', 'foo_value1', 'foo_value2'])
  ->insertInto('bar_table', ['bar_name', 'bar_output1', 'bar_output2'])
  ->onDuplicate(['bar_output1 = foo_value1', 'bar_output2 = foo_value2']);

This parallels the underlying SQL structure. However, it is a bit verbose -- observe that every field on every side of the data-transfer (foo_value1, bar_value1, foo_value2, etc) has to be mentioned multiple times.

The second commit provides a convenience function which does the same thing - but with cleaner notation:

CRM_Utils_SQL_Select::from('foo_table')
  ->syncInto('bar_table', 'bar_name', [
    'bar_name' => 'foo_name',
    'bar_output1' => 'foo_value1',
    'bar_output2' => 'foo_value1',
  ])

[civibot]

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[eileenmcnaughton]

Seems like a straight forward helper & a logical sql function