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(Created page with " ← Back to Full SCM API documentation == tx_commit == Commits the current transaction. '''Allowed number of parameters:''' 1–1 <span id="parameters-2"></span> === Parameters === * '''session''' (<code>func(key:string?, value:any?) -> any</code>): the session function that holds tx state <span id="returns-2"></span> === Returns === <code>bool</code> == tx_rollback == Rolls back the current transaction. '''Allowed number of parameters:''' 1–1 <span...")
 
(Refresh MemCP documentation: accuracy, operational guidance, performance profile and maintained API reference)
 
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<!-- Copyright (C) 2026 Carl-Philip Haensch -->
<!-- SPDX-License-Identifier: GPL-3.0-or-later -->


← Back to [[Full SCM API documentation]]
<span id="transactions"></span>
= Transactions =


<!-- Generated from MemCP c42e19eba on 2026-08-27; do not edit manually. -->
<div class="mw-message-box mw-message-box-notice">Generated from MemCP commit <code>c42e19eba</code> on 27 August 2026. See [[Full SCM API documentation]].</div>
The '''Transactions''' module manages transaction contexts stored in a session. It provides cursor-stability transactions, ACID snapshot/OCC transactions, commit, rollback, and implicit autocommit wrapping.
These functions are runtime primitives used by the SQL frontend. Applications normally use <code>BEGIN</code>, <code>COMMIT</code>, and <code>ROLLBACK</code>; see [[Transactions and Isolation]] for visibility, conflict, and durability semantics.
== tx_begin ==
Begins a new cursor-stability transaction. Takes the session function as argument. Stores the transaction context in the session.
'''Allowed number of parameters:''' 1–1
<span id="parameters"></span>
=== Parameters ===
* '''session''' (<code>func</code>): the session function to store tx state in
** '''Parameters'''
*** '''key''' (<code>string</code>) ''(optional)''
*** '''value''' (<code>any</code>) ''(optional)''
** '''Returns'''
*** '''value''' (<code>any</code>)
<span id="returns"></span>
=== Returns ===
* '''value''' (<code>bool</code>)
== tx_begin_acid ==
Begins a new ACID transaction with snapshot isolation and OCC commit. Takes the session function as argument.
'''Allowed number of parameters:''' 1–1
<span id="parameters-1"></span>
=== Parameters ===
* '''session''' (<code>func</code>): the session function to store tx state in
** '''Parameters'''
*** '''key''' (<code>string</code>) ''(optional)''
*** '''value''' (<code>any</code>) ''(optional)''
** '''Returns'''
*** '''value''' (<code>any</code>)
<span id="returns-1"></span>
=== Returns ===
* '''value''' (<code>bool</code>)


== tx_commit ==
== tx_commit ==
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=== Parameters ===
=== Parameters ===


* '''session''' (<code>func(key:string?, value:any?) -&gt; any</code>): the session function that holds tx state
* '''session''' (<code>func</code>): the session function that holds tx state
** '''Parameters'''
*** '''key''' (<code>string</code>) ''(optional)''
*** '''value''' (<code>any</code>) ''(optional)''
** '''Returns'''
*** '''value''' (<code>any</code>)


<span id="returns-2"></span>
<span id="returns-2"></span>
=== Returns ===
=== Returns ===


<code>bool</code>
* '''value''' (<code>bool</code>)


== tx_rollback ==
== tx_rollback ==
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=== Parameters ===
=== Parameters ===


* '''session''' (<code>func(key:string?, value:any?) -&gt; any</code>): the session function that holds tx state
* '''session''' (<code>func</code>): the session function that holds tx state
** '''Parameters'''
*** '''key''' (<code>string</code>) ''(optional)''
*** '''value''' (<code>any</code>) ''(optional)''
** '''Returns'''
*** '''value''' (<code>any</code>)


<span id="returns-3"></span>
<span id="returns-3"></span>
=== Returns ===
=== Returns ===


<code>bool</code>
* '''value''' (<code>bool</code>)


== with_autocommit ==
== with_autocommit ==
Line 44: Line 105:
=== Parameters ===
=== Parameters ===


* '''session''' (<code>func(key:string?, value:any?) -&gt; any</code>): the session function holding tx state
* '''session''' (<code>func</code>): the session function holding tx state
** '''Parameters'''
*** '''key''' (<code>string</code>) ''(optional)''
*** '''value''' (<code>any</code>) ''(optional)''
** '''Returns'''
*** '''value''' (<code>any</code>)
* '''fn''' (<code>func</code>): zero-argument function to execute
* '''fn''' (<code>func</code>): zero-argument function to execute
** '''Returns'''
*** '''value''' (<code>any</code>)


<span id="returns-4"></span>
<span id="returns-4"></span>
=== Returns ===
=== Returns ===


<code>any</code>
* '''value''' (<code>any</code>)

Latest revision as of 11:59, 28 August 2026


Transactions

Generated from MemCP commit c42e19eba on 27 August 2026. See Full SCM API documentation.

The Transactions module manages transaction contexts stored in a session. It provides cursor-stability transactions, ACID snapshot/OCC transactions, commit, rollback, and implicit autocommit wrapping.

These functions are runtime primitives used by the SQL frontend. Applications normally use BEGIN, COMMIT, and ROLLBACK; see Transactions and Isolation for visibility, conflict, and durability semantics.

tx_begin

Begins a new cursor-stability transaction. Takes the session function as argument. Stores the transaction context in the session.

Allowed number of parameters: 1–1

Parameters

  • session (func): the session function to store tx state in
    • Parameters
      • key (string) (optional)
      • value (any) (optional)
    • Returns
      • value (any)

Returns

  • value (bool)

tx_begin_acid

Begins a new ACID transaction with snapshot isolation and OCC commit. Takes the session function as argument.

Allowed number of parameters: 1–1

Parameters

  • session (func): the session function to store tx state in
    • Parameters
      • key (string) (optional)
      • value (any) (optional)
    • Returns
      • value (any)

Returns

  • value (bool)

tx_commit

Commits the current transaction.

Allowed number of parameters: 1–1

Parameters

  • session (func): the session function that holds tx state
    • Parameters
      • key (string) (optional)
      • value (any) (optional)
    • Returns
      • value (any)

Returns

  • value (bool)

tx_rollback

Rolls back the current transaction.

Allowed number of parameters: 1–1

Parameters

  • session (func): the session function that holds tx state
    • Parameters
      • key (string) (optional)
      • value (any) (optional)
    • Returns
      • value (any)

Returns

  • value (bool)

with_autocommit

Executes fn inside an implicit TxCursorStability transaction if no explicit transaction is active in session. Commits on success, rolls back on error, and re-raises any panic so the caller's error handler still fires. If an explicit transaction is active (session["transaction"] != nil), fn is executed without any wrapping.

Allowed number of parameters: 2–2

Parameters

  • session (func): the session function holding tx state
    • Parameters
      • key (string) (optional)
      • value (any) (optional)
    • Returns
      • value (any)
  • fn (func): zero-argument function to execute
    • Returns
      • value (any)

Returns

  • value (any)
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