START_TRANSACTION(7pg18)

✨ START_TRANSACTION ✨

okay bestie, welcome to the START TRANSACTION(7) page from the PostgreSQL 18.6 docs 💖 this is the manual page for START_TRANSACTION, and it's genuinely so simple you're gonna be like "wait that's it?" 🎀

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🌸 NAME 🌸

START_TRANSACTION — start a transaction block. that's the whole vibe. it opens a block, that's its job, it's giving gatekeeper of the transaction 🔥

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🦋 SYNOPSIS 🦋

START TRANSACTION [ transaction_mode [, ...] ]

where transaction_mode is one of:

ISOLATION LEVEL { SERIALIZABLE | REPEATABLE READ | READ COMMITTED | READ UNCOMMITTED }
READ WRITE | READ ONLY
[ NOT ] DEFERRABLE

like. look at those options. gorgeous. each one is a little personality trait you can give your brand new transaction 💅

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💜 DESCRIPTION 💜

so this command begins a new transaction block. that's it, that's the main character move ✨

and if you specify the isolation level, the read/write mode, or the deferrable mode, then your new transaction literally gets those characteristics — exactly as if you'd run SET TRANSACTION. same energy, same result, no cap 🫶

also: this is the same as the BEGIN command. literally twins. identical. BEGIN walked so START TRANSACTION could run, iykyk 💀

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🎀 PARAMETERS 🎀

ngl bestie, this page is not gonna explain the parameters to you. it's like "go read SET TRANSACTION" (SET_TRANSACTION(7)) for info on what the parameters to this statement actually mean 🙈

so if you're confused about SERIALIZABLE vs REPEATABLE READ vs whatever, that's a different page, go drink your water and click that link 💖

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🌈 COMPATIBILITY 🌈

okay this is where it gets interesting 👑

in the standard, you don't even need to issue START TRANSACTION to start a transaction block — because any SQL command implicitly begins a block. every single one. iconic behaviour, honestly.

so how does PostgreSQL fit into that? PostgreSQL's behaviour can be seen as implicitly issuing a COMMIT after each command that does not follow START TRANSACTION (or BEGIN) — and because of that, people often call it "autocommit" ⭐

other relational database systems might offer an autocommit feature as a convenience. cute for them 💅

heads up: the DEFERRABLE transaction_mode is a PostgreSQL language extension — so don't go expecting it everywhere else, bestie 🚨

also: the SQL standard requires commas between successive transaction_modes, but for historical reasons PostgreSQL allows the commas to be omitted. yes really. she's flexible like that 🌸

and there's more tea — see also the compatibility section of SET TRANSACTION (SET_TRANSACTION(7)) 💜

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👑 SEE ALSO 👑

• BEGIN(7)
• COMMIT(7)
• ROLLBACK(7)
• SAVEPOINT(7)
• SET TRANSACTION (SET_TRANSACTION(7))

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that's the whole page bestie, go start a transaction, you're gonna slay 💖✨

PostgreSQL 18.6 · 2026 — mwah, that's a wrap on START TRANSACTION(7), thanks for coming to my TED talk 🎀🦋💅