“Big Tech” ortamlarda (do, o‘z o‘z o‘z o‘z users, massive datasets, and rapidly evolving requirements), baz bazaya bazadi. Men o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘ UNIQUE INDEX 1. Niyə o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z. Database unique indexes o‘z bilan o‘z, o‘z? son line of defense against data duplication. I used to think so too. Whenever a field in a table needed to be unique, I would casually slapp a unique index on it. Men o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z. O‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z O‘z O‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z. Bu vaxt, master-slave replication lag o‘z rollercoaster, o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z service hiccups. tenant_id is_deleted Daylar Biz o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z. O‘z O‘z sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga sizga siz user@example.com USER@EXAMPLE.COM O‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z Ped o‘z yeni Bu iki operasiyalarni siz necə koordinasiyasiniz? Kimin ilk o‘zingizdir? Bilmizni o‘zingizdirmi? o‘zizni o‘zingizdirmi? o‘zizni o‘zingizdirmi. DROP CREATE O‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z Bu makala o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z. 2. : Niyə o‘z o‘z o‘z o‘z o‘z bizni? UNIQUE INDEX Unix indeks Biz o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z. O‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z. O‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z. Schema as documentation: O‘z shayda o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z. Potensiyal qilmiz performans boost: Kilmiz index, qilmiz bu qilmiz daha sürgidir. O‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z. 3. “Big Tech” lensda: o‘z o‘z bu fayllar hala fayldirmi? UNIQUE INDEX Unix indeks O‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z. "The ultimate safeguard"? Is this safeguard reliable? What exactly is it safeguarding against? It doesn't fully recognize business-level "duplicates"! Except the email case sensitivity issue I mentioned earlier (which could be solved by using but introduce more complexity in the DB layer), or phone numbers with or without , or usernames with or without special characters stripped... these nuances, which business logic considers "the same," are beyond the grasp of a database's simplistic "byte-for-byte identical" unique index. It can't prevent "logical duplicates" at the business layer. collation +44 The application layer has to do the heavy lifting anyway. Since all these complex "sameness" checks must be handled in the application code (you can't just throw raw database errors at users, can you?), the application layer is the true workhorse ensuring "business data uniqueness." The database's unique index is, at best, an "auxiliary police officer" whose standards might not even align with the business rules. In distributed systems, it's merely a "local bodyguard." Once you shard your tables in a distributed scenario, an in-table unique index can't ensure global uniqueness. Global uniqueness then relies on ID generation services or application-level global validation. At this point, the "safeguard" provided by the local database index becomes even less significant. This "ultimate safeguard" might miss the mark, has limited coverage, and relying solely on it is a bit precarious. "Easy to implement"? One-time setup, week-long headache. Adding a unique index to a brand new table is indeed just one SQL statement. But more often, you're changing the rules for an old table that's been running for ages and has accumulated mountains of data. Trying to alter a unique index on a table with tens of millions of rows (e.g., changing from a single-field unique to a composite unique) could mean several minutes of table locking! Online DDL tools might save you from service downtime, but the entire process can still be lengthy, resource-intensive, and risky. Agile? Not so fast! In scenarios with rapid iteration, multi-region synchronization, and compliance requirements, a single unique index change at the database level can hold you up for days. So much for agility. So, that initial "simplicity" is like bait compared to the "hell" of modifying it later. "Schema as documentation"? The documentation might not match reality! Yes, a unique index in the table structure acts as a form of "technical documentation." But "documentation" can be misleading. If the "uniqueness" defined by this index doesn't align with the actual, more complex business rules (like the case-insensitivity example), then this "documentation" is not only useless but can also mislead future developers. If changing this "documentation" (i.e., modifying the unique index) involves an epic struggle, why not write down the business rules properly in actual design documents, wikis, or code comments? Those are far easier to update. "A potential query performance boost"? Is the tail wagging the dog? This is a common misconception, or rather, an overemphasized "added value." If you simply want to speed up queries on a specific field or set of fields, you can absolutely create a regular, non-unique index for them! A non-unique index will boost query speeds just fine, and it comes without the write overhead, DDL pains, and rigid business logic constraints of a unique index. Master-slave index inconsistency can instantly "paralyze" replication: I've seen it happen multiple times: the unique index configuration on the primary database is updated (e.g., a field is added, or a constraint is changed), but the index on the replica isn't modified in sync. Then, as soon as data changes on the primary (e.g., a row is inserted that would be considered a duplicate on the replica, or the primary can write it but the replica can't due to the incorrect/outdated index), the binlog is applied to the replica, and bam! . Replication just dies. When this happens, you get data lag, read-write splitting is affected, and it can even impact failover capabilities. What a nightmare, right? Slave_SQL_Running: No 4.Let the application layer do the job—It’s what it’s good at! Bu problemlar bazada unikal indekslar, data unicity qilmadi qilmadi qilmadi qilmadi app layer. O‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z: Flexible and Precise: Ko‘r bizni definishib dubbi, biz logiki coding - cas sensitivity, formating, kompleks ko‘rlar, siz o‘z. Better User Experience: If a user makes a mistake, we can provide clear, helpful feedback, such as "This phone number is already registered. Would you like to log in instead?" as a cold, cryptic database error. Efficient Early Rejection: Intercept duplicates on the service interface layer or even the gateway layer, o‘z data o‘z o‘z bazayda, o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z. Interface Idempotency: Bu, duplicate operations bo‘ladi. If a user double-clicks the submit button, or a network issue causes a retry, proper idempotency at the application layer ensures data is not duplicated. A unique index can’t help with this. Konkurs U bilan o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o‘z o
