MONGOC_COLLECTION_SAVE(3)

💖 MONGOC_COLLECTION_SAVE 💖

okay so bestie, we're in libmongoc land and the page is literally called MONGOC_COLLECTION_SAVE(3). yes it's a whole manual page, no it's not scary, and yes i'm gonna walk you through it like we're texting at 2am 🫶

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🚨 WARNING 🚨

Deprecated since version 1.9.0: Use mongoc_collection_insert_one() or mongoc_collection_replace_one() with "upsert" instead.

not me having to tell you this function is lowkey retired 💀 it's giving "still works but the group chat has moved on". use the newer ones, i'm begging.

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✨ SYNOPSIS ✨

bool
mongoc_collection_save (mongoc_collection_t *collection,
                        const bson_t *document,
                        const mongoc_write_concern_t *write_concern,
                        bson_error_t *error);

look at that signature, it's iconic, it's neat, it's literally right there 👑

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🎀 PARAMETERS 🎀

• collection — a mongoc_collection_t. that's the collection we're saving into, the main character of the operation ngl.
• document — a bson_t holding the document. this is the actual content, the vibe, the payload.
• write_concern — a mongoc_write_concern_t, or NULL if you want the default write concern. pass NULL and let the default handle it, no thoughts head empty, it's fine 🌸
• error — an optional spot to put a bson_error_t, or NULL. optional means optional, so if you don't care about the tea, pass NULL 🙈

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🌈 DESCRIPTION 🌈

so this function shall save a document into collection. and here's the lil plot twist that makes it save and not just insert:

• if the document has an _id field, it will be updated ✨
• otherwise, it will be inserted 🦋

that's it. that's the whole trick. update-if-it-has-an-id, insert-if-it-doesn't. periodt 💅

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😭 ERRORS 😭

errors get propagated through the error parameter. so if something goes sideways, that's where you'll find out what happened, bestie.

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⭐ RETURNS ⭐

returns true if it worked. slay.

returns false and sets error if:

• there are invalid arguments, or
• there's a server error or a network error.

heads up, this one's important: a write concern timeout or a write concern error counts as a failure. so like, false energy, not true energy. don't get it twisted 💀

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👑 AUTHOR 👑

MongoDB, Inc

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🧚 COPYRIGHT 🧚

2009-present, MongoDB, Inc.

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and that's the whole page, bestie 💖 you ate. this was libmongoc version 1.30.13, dated Oct 09, 2026, and the page itself is MONGOC_COLLECTION_SAVE(3). go forth and use mongoc_collection_insert_one() or mongoc_collection_replace_one() with "upsert" instead, fr fr 🌸✨🫶