PHP array merge values from one array into another : <p>Sorry I have read so many posts to make sense of this and have finally confused myself!</p>

<p>I have 2 arrays:</p>

<p>Array 1:</p>

<pre><code>Array (

[0] =&gt; Array ( [ID] =&gt; SI012348 [Date] =&gt; 06/01/2016 [Month] =&gt; 1 [Tier1] =&gt; 2.188875 [Tier2] =&gt; [Tier3] =&gt; [Tier4] =&gt; [Delivery] =&gt; 0 ) 

[1] =&gt; Array ( [ID] =&gt; SI012351 [Date] =&gt; 06/01/2016 [Month] =&gt; 1 [Tier1] =&gt; 2.139 [Tier2] =&gt; 0 [Tier3] =&gt; 0 [Tier4] =&gt; 0 [Delivery] =&gt; 0 ) 

[2] =&gt; Array ( [ID] =&gt; SI012387 [Date] =&gt; 14/01/2016 [Month] =&gt; 1 [Tier1] =&gt; 0.201 [Tier2] =&gt; 0 [Tier3] =&gt; 0 [Tier4] =&gt; 0 [Delivery] =&gt; 0 ) 

)
</code></pre>

<p>Array 2: (Contains all invoices with Delivery charges)</p>

<pre><code>Array ( 
[SI000005] =&gt; 25 
[SI000010] =&gt; 15 
[SI000054] =&gt; 20 
[SI000069] =&gt; 0 
[SI000074] =&gt; 20 
[SI000076] =&gt; 16
)
</code></pre>

<p>I need to update Array 1 where SI00000x matches and push the value from Array 2 into the [Delivery] value in Array 1.</p>

<p>I am sure this is straightforward but everything I try either takes an age or crashes!</p>

<p>Please help!   </p>
