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pengxiangyu 7592f52d2e [Feature][Insert] Add transaction for the operation of insert #6244 (#6245) 
## Proposed changes
Add transaction for the operation of insert. It will cost less time than non-transaction(it will cost 1/1000 time) when you want to insert a amount of rows.
### Syntax

```
BEGIN [ WITH LABEL label];
INSERT INTO table_name ...
[COMMIT | ROLLBACK];
```

### Example
commit a transaction:
```
begin;
insert into Tbl values(11, 22, 33);
commit;
```
rollback a transaction:
```
begin;
insert into Tbl values(11, 22, 33);
rollback;
```
commit a transaction with label:
```
begin with label test_label;
insert into Tbl values(11, 22, 33);
commit;
```

### Description
```
begin:  begin a transaction, the next insert will execute in the transaction until commit/rollback;
commit:  commit the transaction, the data in the transaction will be inserted into the table;
rollback:  abort the transaction, nothing will be inserted into the table;
```
### The main realization principle:
```
1. begin a transaction in the session. next sql is executed in the transaction;
2. insert sql will be parser and get the database name and table name, they will be used to select a be and create a pipe to accept data;
3. all inserted values will be sent to the be and write into the pipe;
4. a thread will get the data from the pipe, then write them to disk;
5. commit will complete this transaction and make these data visible;
6. rollback will abort this transaction
```

### Some restrictions on the use of update syntax.
1. Only ```insert``` can be called in a transaction.
2. If something error happened, ```commit``` will not succeed, it will ```rollback``` directly;
3. By default, if part of insert in the transaction is invalid, ```commit``` will only insert the other correct data into the table.
4. If you need ```commit``` return failed when any insert in the transaction is invalid, you need execute ```set enable_insert_strict = true``` before ```begin```.
2021-07-21 10:54:11 +08:00

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title, language
title language
BEGIN en

BEGIN, COMMIT, ROLLBACK

Description

Syntax

BEGIN;
INSERT INTO table_name ...
COMMIT;

BEGIN [ WITH LABEL label];
INSERT INTO table_name ...
ROLLBACK;

Parameters

label: the label for this transaction, if you need to set it to a string.

Note

A transaction can only be used on insert, nor update or delete. You can check the state of this transaction by SHOW TRANSACTION WHERE LABEL = 'label'

example

  1. Begin a transaction without a label, then commit it
BEGIN
INSERT INTO test VALUES (1, 2);
INSERT INTO test (c1, c2) VALUES (1, 2);
INSERT INTO test (c1, c2) VALUES (1, DEFAULT);
INSERT INTO test (c1) VALUES (1);
COMMIT:

All the data in the sql between begin and commit will be inserted into the table.

  1. Begin a transaction without a label, then abort it
BEGIN
INSERT INTO test VALUES (1, 2);
INSERT INTO test (c1, c2) VALUES (1, 2);
INSERT INTO test (c1, c2) VALUES (1, DEFAULT);
INSERT INTO test (c1) VALUES (1);
ROLLBACK:

All the data in the sql between begin and rollback will be aborted, nothing will be inserted into the table.

  1. Begin a transaction with a label, then commit it
BEGIN WITH LABEL test_label1
INSERT INTO test VALUES (1, 2);
INSERT INTO test (c1, c2) VALUES (1, 2);
INSERT INTO test (c1, c2) VALUES (1, DEFAULT);
INSERT INTO test (c1) VALUES (1);
COMMIT:

All the data in the sql between begin and commit will be inserted into the table. The label of test_label1 will be set to mark this transaction. You can check this transaction by SHOW TRANSACTION WHERE LABEL = 'test_label1'.

keyword

BEGIN, COMMIT, ROLLBACK