Shadow

Shadow #

Syntax	Description
CREATE SHADOW RULE shadowRuleDefinition [, shadowRuleDefinition] …	Create shadow rule
ALTER SHADOW RULE shadowRuleDefinition [, shadowRuleDefinition] …	Modify shadow rule
DROP SHADOW RULE ruleName [, ruleName] …	Delete shadow rule
SHOW SHADOW shadowRule	RULES [FROM databaseName]
SHOW SHADOW TABLE RULES [FROM databaseName]	View shadow table
COUNT SHADOW RULE	Count the number of shadow rules, this syntax will be deprecated in subsequent versions
DROP SHADOW ALGORITHM algorithmName [, algorithmName] …	Delete shadow algorithm
SHOW SHADOW ALGORITHMS [FROM databaseName]	View shadow algorithm
CREATE DEFAULT SHADOW ALGORITHM shadowAlgorithm	Create default shadow algorithm
ALTER DEFAULT SHADOW ALGORITHM shadowAlgorithm	Modify default shadow algorithm
DROP DEFAULT SHADOW ALGORITHM [IF EXISTS]	Delete default shadow algorithm
SHOW DEFAULT SHADOW ALGORITHM	View default shadow algorithm

1. Create Shadow Algorithm #

CREATE SHADOW RULE shadowRuleDefinition [, shadowRuleDefinition] ... 

shadowRuleDefinition: ruleName(storageUnitMapping, shadowTableRule [, shadowTableRule] ...)

storageUnitMapping: SOURCE=storageUnitName, SHADOW=storageUnitName

shadowTableRule: tableName(shadowAlgorithm [, shadowAlgorithm] ...)

shadowAlgorithm: TYPE(NAME=shadowAlgorithmType, PROPERTIES([algorithmProperties] ...))

algorithmProperties: algorithmProperty [, algorithmProperty] ... 

algorithmProperty: key=value

Parameter Description

Name	Data type	Description
ruleName	IDENTIFIER	Rule name
storageUnitName	IDENTIFIER	Storage unit name
tableName	IDENTIFIER	Shadow table name
algorithmName	IDENTIFIER	Shadow algorithm name
shadowAlgorithmType	STRING	Shadow algorithm type

Duplicate ruleName cannot be created
storageUnitMapping specifies the mapping relationship between the source database and the shadow library. You need to use the storage unit managed by RDL, please refer to storage unit
shadowAlgorithm can act on multiple shadowTableRule at the same time
shadowAlgorithmType please refer to shadow built-in algorithms
shadowTableRule can be reused by different shadowRuleDefinition, so when executing DROP SHADOW RULE, the corresponding shadowTableRule will not be removed
shadowAlgorithm can be reused by different shadowTableRule, so when executing ALTER SHADOW RULE, the corresponding shadowAlgorithm will not be removed
algorithmName will be automatically generated according to ruleName, tableName, shadowAlgorithmType and algorithm collection index. The default name is default_shadow_algorithm.
Example

  CREATE SHADOW RULE shadow_rule(
SOURCE=demo_ds,
SHADOW=demo_ds_shadow,
t_order(TYPE(NAME="SIMPLE_HINT", PROPERTIES("shadow"="true", "foo"="bar")),TYPE(NAME="REGEX_MATCH", PROPERTIES("operation"="insert","column"="user_id", "regex"='[1]'))), 
t_order_item(TYPE(NAME="VALUE_MATCH", PROPERTIES("operation"="insert","column"="user_id", "value"='1'))));

2. Modify Shadow Rule #

ALTER SHADOW RULE shadowRuleDefinition [, shadowRuleDefinition] ... 

shadowRuleDefinition: ruleName(storageUnitMapping, shadowTableRule [, shadowTableRule] ...)

storageUnitMapping: SOURCE=storageUnitName, SHADOW=storageUnitName

shadowTableRule: tableName(shadowAlgorithm [, shadowAlgorithm] ...)

shadowAlgorithm: TYPE(NAME=shadowAlgorithmType, PROPERTIES([algorithmProperties] ...))

algorithmProperties: algorithmProperty [, algorithmProperty] ... 

algorithmProperty: key=value

Parameter Description

Name	Data type	Description
ruleName	IDENTIFIER	Rule name
storageUnitName	IDENTIFIER	Storage unit name
tableName	IDENTIFIER	Shadow table name
algorithmName	IDENTIFIER	Shadow algorithm name
shadowAlgorithmType	STRING	Shadow algorithm type

storageUnitMapping specifies the mapping relationship between the source database and the shadow library. You need to use the storage unit managed by RDL, please refer to storage unit
shadowAlgorithm can act on multiple shadowTableRule at the same time
shadowAlgorithmType currently supports VALUE_MATCH, REGEX_MATCH and SIMPLE_HINT
shadowTableRule can be reused by different shadowRuleDefinition, so when executing DROP SHADOW RULE, the corresponding shadowTableRule will not be removed
shadowAlgorithm can be reused by different shadowTableRule, so when executing ALTER SHADOW RULE, the corresponding shadowAlgorithm will not be removed
algorithmName will be automatically generated according to ruleName, tableName, shadowAlgorithmType and algorithm collection index. The default name is default_shadow_algorithm.

Example

ALTER SHADOW RULE shadow_rule(
SOURCE=demo_ds,
SHADOW=demo_ds_shadow,
t_order(TYPE(NAME="SIMPLE_HINT", PROPERTIES("shadow"="true", "foo"="bar")),TYPE(NAME="REGEX_MATCH", PROPERTIES("operation"="insert","column"="user_id", "regex"='[1]'))), 
t_order_item(TYPE(NAME="VALUE_MATCH", PROPERTIES("operation"="insert","column"="user_id", "value"='1'))));

3. Delete Shadow Rule #

DROP SHADOW RULE ruleName [, ruleName] ...

Parameter Description

Name	Data type	Description
ruleName	IDENTIFIER	Rule name

Example

DROP SHADOW RULE shadow_rule;

4. View Shadow Rule #

SHOW SHADOW shadowRule | RULES [FROM databaseName]
shadowRule: 
    RULE ruleName

Parameter Description

Name	Data type	Description
ruleName	IDENTIFIER	Rule name

Example

View all shadow rule

mysql> SHOW SHADOW RULES;
+--------------------+-------------+-------------+--------------+
| rule_name          | source_name | shadow_name | shadow_table |
+--------------------+-------------+-------------+--------------+
| shadow_rule_1      | ds_1        | ds_shadow_1 | t_order      |
| shadow_rule_2      | ds_2        | ds_shadow_2 | t_order_item |
+--------------------+-------------+-------------+--------------+
2 rows in set (0.02 sec)

View specified shadow rule

mysql> SHOW SHADOW RULE shadow_rule_1;
+------------------+-------------+-------------+--------------+
| rule_name        | source_name | shadow_name | shadow_table |
+------------------+-------------+-------------+--------------+
| shadow_rule_1    | ds_1        | ds_shadow_1 | t_order      |
+------------------+-------------+-------------+--------------+
1 rows in set (0.01 sec)

Output Description

Column	Description
rule_name	Rule name
source_name	Source database
shadow_name	Shadow database
shadow_table	Shadow table

5. View Shadow Table Rule #

SHOW SHADOW TABLE RULES [FROM databaseName]

Example

mysql> SHOW SHADOW TABLE RULES;
+--------------+--------------------------------------------------------------------------------+
| shadow_table | shadow_algorithm_name                                                          |
+--------------+--------------------------------------------------------------------------------+
| t_order_1    | user_id_match_algorithm,simple_hint_algorithm_1                                |  
+--------------+--------------------------------------------------------------------------------+
1 rows in set (0.01 sec)

Output Description

Column	Description
shadow_table	Shadow table
shadow_algorithm_name	Shadow algorithm name

6. Delete Shadow Algorithm #

DROP SHADOW ALGORITHM algorithmName [, algorithmName] ...

Parameter Description

Name	Data type	Description
algorithmName	IDENTIFIER	Shadow algorithm name

shadowAlgorithm can be reused by different shadowTableRule, so when executing ALTER SHADOW RULE, the corresponding shadowAlgorithm will not be removed
In used shadowAlgorithm cannot be dropped

7. View Shadow Algorithm #

SHOW SHADOW ALGORITHMS [FROM databaseName]

Example

mysql> SHOW SHADOW ALGORITHMS;
+-------------------------+--------------------+-------------------------------------------+----------------+
| shadow_algorithm_name   | type               | props                                     | is_default     |
+-------------------------+--------------------+-------------------------------------------+----------------+
| user_id_match_algorithm | REGEX_MATCH        | operation=insert,column=user_id,regex=[1] | false          |
| simple_hint_algorithm_1 | SIMPLE_HINT        | shadow=true,foo=bar                       | false          |
+-------------------------+--------------------+-------------------------------------------+----------------+
2 rows in set (0.01 sec)

Output Description

Column	Description
shadow_algorithm_name	Shadow algorithm name
type	Algorithm type
props	Algorithm properties
is_default	Whether default

8. Create Default Shadow Algorithm #

CREATE DEFAULT SHADOW ALGORITHM shadowAlgorithm

shadowAlgorithm: TYPE(NAME=shadowAlgorithmType, PROPERTIES([algorithmProperties] ...))

algorithmProperties: algorithmProperty [, algorithmProperty] ... 

algorithmProperty: key=value

Parameter Description

Column	Data type	Description
shadow_algorithm_name	IDENTIFIER	Shadow algorithm name
type	STRING	Algorithm type

shadowAlgorithm can be reused by different shadowTableRule, so when executing ALTER SHADOW RULE, the corresponding shadowAlgorithm will not be removed
algorithmName will be automatically generated according to ruleName, tableName, shadowAlgorithmType and algorithm collection index. The default name is default_shadow_algorithm.

Example

CREATE DEFAULT SHADOW ALGORITHM TYPE(NAME="SIMPLE_HINT", PROPERTIES("shadow"="true", "foo"="bar");

9. Modify Default Shadow Algorithm #

ALTER DEFAULT SHADOW ALGORITHM shadowAlgorithm

shadowAlgorithm: TYPE(NAME=shadowAlgorithmType, PROPERTIES([algorithmProperties] ...))

algorithmProperties: algorithmProperty [, algorithmProperty] ... 

algorithmProperty: key=value

Parameter Description

Column	Data type	Description
shadow_algorithm_name	IDENTIFIER	Shadow algorithm name
type	STRING	Algorithm type

shadowAlgorithm can be reused by different shadowTableRule, so when executing ALTER SHADOW RULE, the corresponding shadowAlgorithm will not be removed
algorithmName will be automatically generated according to ruleName, tableName, shadowAlgorithmType and algorithm collection index. The default name is default_shadow_algorithm.

Example

ALTER DEFAULT SHADOW ALGORITHM TYPE(NAME="SIMPLE_HINT", PROPERTIES("shadow"="false", "foo"="bar");

10. Delete Default Shadow Algorithm #

DROP DEFAULT SHADOW ALGORITHM [IF EXISTS]

Parameter Description

None

Example

DROP DEFAULT SHADOW ALGORITHM;

11. View Default Shadow Algorithm #

SHOW DEFAULT SHADOW ALGORITHM;

Parameter Description

None

Example

SHOW DEFAULT SHADOW ALGORITHM;