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	 d20a96f9c1
			
		
	
	
	d20a96f9c1
	
	
	
		
			
			In MariaDB, we have a confusing problem where: * The transaction_isolation option can be set in a configuration file, but it cannot be set dynamically. * The tx_isolation system variable can be set dynamically, but it cannot be set in a configuration file. Therefore, we have two different names for the same thing in different contexts. This is needlessly confusing, and it complicates the documentation. The same thing applys for transaction_read_only. MySQL 5.7 solved this problem by making them into system variables. https://dev.mysql.com/doc/relnotes/mysql/5.7/en/news-5-7-20.html This commit takes a similar approach by adding new system variables and marking the original ones as deprecated. This commit also resolves some legacy problems related to SET STATEMENT and transaction_isolation.
		
			
				
	
	
		
			68 lines
		
	
	
	
		
			2.7 KiB
		
	
	
	
		
			Text
		
	
	
	
	
	
			
		
		
	
	
			68 lines
		
	
	
	
		
			2.7 KiB
		
	
	
	
		
			Text
		
	
	
	
	
	
| --echo #
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| --echo # MDEV-21921 Make transaction_isolation and transaction_read_only into
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| --echo # system variables
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| --echo #
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| 
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| SET @saved_global_isolation= @@global.transaction_isolation;
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| SET @saved_global_read_only= @@global.transaction_read_only;
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| 
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| --echo # Case 1: Check the influence of --transaction_* on
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| --echo # @@session.transaction_* and @@global.transaction_*,
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| --echo # @@session.tx_*, @@global.tx_*.
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| 
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| SELECT @@session.transaction_isolation, @@global.transaction_isolation,
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|        @@session.tx_isolation, @@global.tx_isolation;
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| SHOW GLOBAL VARIABLES LIKE '%_isolation';
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| SHOW SESSION VARIABLES LIKE '%_isolation';
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| 
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| SELECT @@session.transaction_read_only, @@global.transaction_read_only,
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|        @@session.tx_read_only, @@global.tx_read_only;
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| SHOW GLOBAL VARIABLES LIKE '%_read_only';
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| SHOW SESSION VARIABLES LIKE '%_read_only';
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| 
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| --echo # Case 2: Check that the change to tx_* is reflected to transaction_*.
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| 
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| SET tx_isolation= 'REPEATABLE-READ';
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| SET @@global.tx_isolation= 'SERIALIZABLE';
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| SELECT @@session.tx_isolation, @@global.tx_isolation,
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| @@session.transaction_isolation, @@global.transaction_isolation;
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| SHOW GLOBAL VARIABLES LIKE '%_isolation';
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| SHOW SESSION VARIABLES LIKE '%_isolation';
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| 
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| SET STATEMENT tx_isolation= 'SERIALIZABLE' FOR SHOW SESSION VARIABLES LIKE '%_isolation';
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| SHOW SESSION VARIABLES LIKE '%_isolation';
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| 
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| SET tx_read_only= OFF;
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| SET @@global.tx_read_only= ON;
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| SELECT @@session.tx_read_only, @@global.tx_read_only,
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| @@session.transaction_read_only, @@global.transaction_read_only;
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| SHOW GLOBAL VARIABLES LIKE '%_read_only';
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| SHOW SESSION VARIABLES LIKE '%_read_only';
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| 
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| SET STATEMENT tx_read_only= ON FOR SHOW SESSION VARIABLES LIKE '%_read_only';
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| SHOW SESSION VARIABLES LIKE '%_read_only';
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| 
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| --echo # Case 3: Check that the change to transaction_* is reflected to tx_*.
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| 
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| SET transaction_isolation= 'SERIALIZABLE';
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| SET @@global.transaction_isolation= 'REPEATABLE-READ';
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| SELECT @@session.tx_isolation, @@global.tx_isolation,
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| @@session.transaction_isolation, @@global.transaction_isolation;
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| SHOW GLOBAL VARIABLES LIKE '%_isolation';
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| SHOW SESSION VARIABLES LIKE '%_isolation';
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| 
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| SET STATEMENT transaction_isolation= 'REPEATABLE-READ' FOR SHOW SESSION VARIABLES LIKE '%_isolation';
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| SHOW SESSION VARIABLES LIKE '%_isolation';
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| 
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| SET transaction_read_only= ON;
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| SET @@global.transaction_read_only= OFF;
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| SELECT @@session.tx_read_only, @@global.tx_read_only,
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| @@session.transaction_read_only, @@global.transaction_read_only;
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| SHOW GLOBAL VARIABLES LIKE '%_read_only';
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| SHOW SESSION VARIABLES LIKE '%_read_only';
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| 
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| SET STATEMENT transaction_read_only= OFF FOR SHOW SESSION VARIABLES LIKE '%_read_only';
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| SHOW SESSION VARIABLES LIKE '%_read_only';
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| 
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| SET @@global.transaction_isolation= @saved_global_isolation;
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| SET @@global.transaction_read_only= @saved_global_read_only;
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