placeholder-type=none environment When loading a configuration file containing environment variables, users need to set place- holder-type to environment, which is commonly used in Docker Image deployment format is basically the same as YAML configuration. Assume that the following set of environment variables exists, 1. The existing environment variable FIXTURE_JDBC_URL is jdbc:h2:mem:foo_ds_1; DB_CLO MODE=MySQL username: sa password: In real situations, system variables are usually defined dynamically. Assume that none of the above system variables are defined, and there is a YAML file config.yaml containing

native-image/shardingsphere-test-native-test-metadata/ folder. ${} contains the reg‐ ular system variables of POM 4.0 corresponding to the relevant submodules, which can be replaced by yourself. git clone ShardingSphere document SET DIST VARIABLE Description The SET DIST VARIABLE syntax is used to set system variables. ### Syntax SetDistVariable ::= 'SET' 'DIST' 'VARIABLE' (proxyPropertyName '=' proxyPropertyValue The SHOW DIST VARIABLE syntax is used to query PROXY system variables configuration. Syntax ShowDistVariable ::= 'SHOW' 'DIST' ('VARIABLES' ('LIKE' likePattern)?| 'VARIABLE' 'WHERE' 'NAME' '=' variableName)

basics of procedural and object-oriented programming − control structures, data structures and variables, classes, objects, etc. To understand JAVA in detail you can go through our JAVA Tutorial. MYBATIS #{id}; To invoke the update query, instantiate Student class, set the values for the variables representing columns which need to be updated, and pass this object as parameter to update method foreach Statement The foreach element allows you to specify a collection and declare item and index variables that can be used inside the body of the element. It also allows you to specify opening and closing

en‐ abled, the default value is false SET VARI‐ ABLE agent_plu gins_enabled = TRUE SHOW ALL VARIABLES Query proxy all properties configura‐ tion SHOW ALL VARI‐ ABLES SHOW VARIABLE variable_name Execute the following SQL to confirm whether binlog is turned on or not: show variables like '%log_bin%'; show variables like '%binlog%'; As shown below, it means binlog has been turned on: +------ To better understand, the Token of keywords in abstract syntax tree is shown in green; that of variables is shown in red; what’s to be further divided is shown in grey. At last, through traversing the

is false SET VARIABLE agent_plug ins_enabled = TRUE SHOW ALL VARIABLES Query proxy all properties configuration SHOW ALL VARIABLES SHOW VARIABLE vari‐ able_name Query proxy variable, name is split max_connections=600 Run the following command and check whether binlog is enabled. show variables like '%log_bin%'; show variables like '%binlog%'; If the following information is displayed, binlog is enabled Syntax Tree) is as follows: The tokens for keywords in the AST are green, while the tokens for variables are red, and gray ones indicate that further splitting is required. Finally, the domain model

is false SET VARIABLE agent_plu gins_enabled = TRUE SHOW ALL VARIABLES Query proxy all properties configuration SHOW ALL VARIABLES SHOW VARIABLE vari‐ able_name Query proxy variable, name is split max_connections=600 Run the following command and check whether binlog is enabled. show variables like '%log_bin%'; show variables like '%binlog%'; If the following information is displayed, binlog is enabled Syntax Tree) is as follows: The tokens for keywords in the AST are green, while the tokens for variables are red, and gray ones indicate that further splitting is required. Finally, the domain model

en‐ abled, the default value is false SET VARI‐ ABLE agent_plu gins_enabled = TRUE SHOW ALL VARIABLES Query proxy all properties configu‐ ration SHOW ALL VARI‐ ABLES SHOW VARIABLE variable_name Execute the following SQL to confirm whether binlog is turned on or not: show variables like '%log_bin%'; show variables like '%binlog%'; As shown below, it means binlog has been turned on: +------ To better understand, the Token of keywords in abstract syntax tree is shown in green; that of variables is shown in red; what’s to be further divided is shown in grey. At last, through traversing the

VARIABLE 描述 SHOW DIST VARIABLE 语法用于查询 PROXY 系统变量配置。 语法 ShowDistVariable ::= 'SHOW' 'DIST' ('VARIABLES' ('LIKE' likePattern)?| 'VARIABLE' 'WHERE' 'NAME' '=' variableName) likePattern ::= string variableName ShardingSphere-Proxy 327 Apache ShardingSphere document 示例 • 查询所有 PROXY 系统变量配置 SHOW DIST VARIABLES; mysql> SHOW DIST VARIABLES; +---------------------------------------+-----------------+ | variable_name | 00 sec) 9.2. ShardingSphere-Proxy 328 Apache ShardingSphere document 保留字 SHOW、DIST、VARIABLE、VARIABLES、NAME 相关链接 • 保留字 REFRESH TABLE METADATA 描述 REFRESH TABLE METADATA 语法用于刷新表元数据。 语法 RefreshTableMetadata

VARIABLE 描述 SHOW DIST VARIABLE 语法用于查询 PROXY 系统变量配置。 语法 ShowDistVariable ::= 'SHOW' 'DIST' ('VARIABLES' ('LIKE' likePattern)?| 'VARIABLE' 'WHERE' 'NAME' '=' variableName) likePattern ::= string variableName ShardingSphere-Proxy 310 Apache ShardingSphere document 示例 • 查询所有 PROXY 系统变量配置 SHOW DIST VARIABLES; mysql> SHOW DIST VARIABLES; +---------------------------------------+-----------------+ | variable_name | 00 sec) 9.2. ShardingSphere-Proxy 311 Apache ShardingSphere document 保留字 SHOW、DIST、VARIABLE、VARIABLES、NAME 相关链接 • 保留字 REFRESH TABLE METADATA 描述 REFRESH TABLE METADATA 语法用于刷新表元数据。 语法 RefreshTableMetadata

VARIABLE 描述 SHOW DIST VARIABLE 语法用于查询 PROXY 系统变量配置。 语法 ShowDistVariable ::= 'SHOW' 'DIST' ('VARIABLES' ('LIKE' likePattern)?| 'VARIABLE' 'WHERE' 'NAME' '=' variableName) likePattern ::= string variableName 补充说明 • 未指定 vairableName 时，默认查询所有 PROXY 系统变量配置 示例 • 查询所有 PROXY 系统变量配置 SHOW DIST VARIABLES; mysql> SHOW DIST VARIABLES; +---------------------------------------+-----------------+ | variable_name | | false | +---------------+----------------+ 1 row in set (0.00 sec) 保留字 SHOW、DIST、VARIABLE、VARIABLES、NAME 相关链接 • 保留字 REFRESH TABLE METADATA 描述 REFRESH TABLE METADATA 语法用于刷新表元数据。 语法 RefreshTableMetadata