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How to save serialization for WP meta query?
Instead, save serialization for data that you do not intend to query in that nature, but instead would only access in a passive fashion by the direct WP API call get_post_meta () – from that function you can unpack a serialized entry to access its array properties too.
Is there way to build meta queries with arrays as a meta _ key?
Is there a way to build meta queries with arrays as a meta_key ? If the value in the database is a string and you want to feed the query several values:
What happens when an object is de-serialized in WordPress?
This is because when the object is de-serialized, an object is created, and all its wake up methods and constructors get executed. This might not seem like a big deal until a user manages to sneak a carefully crafted input, leading to remote code execution when the data is read from the database and de-serialized by WordPress.
Do you have to give WP an array?
You might be tempted to give WP an array, or to turn it into a comma separated list, but you don’t have to! Post meta keys are not unique, you can store the same key multiple times, e.g.: But how do I get the data back out? Have you ever noticed how calls to get_post_meta have a 3rd parameter that’s always set to true? Set it to false:
How to select data from serialized array in MySQL?
The easiest way to remove that is with another SUBSTRING_INDEX call: This time we want to search for the first occurrence of the delimiter, but using a negative number we can tell the function to return all the string after the delimiter, instead of before it. That’s it, a quick approach to selecting data from a serialized array using MySQL.
Is it safe to serialize data in WordPress?
Serialised data is an attack vector, and a major performance issue. I strongly recommend you unserialise your data and modify your save routine. Something similar to this should convert your data to the new format:
Can you store a transaction record in post meta?
LIKE will only work for specific limited situations that are unrealistic, and carries a heavy performance penalty. You might want to store a transaction record in post meta, or some other kind of data structure in user meta, then run into the problem above.
When to use a meta query in WordPress?
meta_query (array) – Contains one or more arrays with the following keys: key (string) – Custom field key. value (string | array) – Custom field value. It can be an array only when compare is ‘IN’, ‘NOT IN’, ‘BETWEEN’, or ‘NOT BETWEEN’.
Can you store multiple rows of post meta in WordPress?
WordPress permits you to store multiple rows of the same post meta for a single post, so you can get an array of data without needing to serialize it and store it in one key. To do this, you need to slightly change how you’re interacting with the post meta api here.
Can you store user IDs in a serialized array?
Have a look at @sMyle’s and at @Kaji’s excellent answers as well. To go off of Johannes’ response, since it is a serialized array, if you happen to be storing something like user id’s (which was my case), you may need to handle it a little differently.