ApplyVSchema command applies the specified VSchema to the keyspace. The VSchema can be specified as a string or in a file. RebuildVSchemaGraph The RebuildVSchemaGraph command propagates the global VSchema values are strictly lower than it. Vitess always converts sharding keys to a left-justified binary string for computing a shard. This left-justification makes the right-most zeroes insignificant and optional Caller ID: It represents the secure client identity when it enters the Vitess side: – It is a single string, represents the user connecting to Vitess (vtgate). – It is authenticated by the transport layer

underlying database names do not have to be equal. Vitess will rewrite these calls to use the literal string for the keyspace name. (This also applies to the synonym SCHEMA()) • ROW_COUNT() and FOUND_ROWS() ApplyVSchema command applies the specified VSchema to the keyspace. The VSchema can be specified as a string or in a file. RebuildVSchemaGraph The RebuildVSchemaGraph command propagates the global VSchema values are strictly lower than it. Vitess always converts sharding keys to a left-justified binary string for computing a shard. This left-justification makes the right-most zeroes insignificant and optional

nonsql_security_fld Column has non-SQL security class defined -84 335544668 dsql_procedure_use_err Procedure <string> does not return any values -85 335544747 usrname_too_long The username entered is too long. Maximum invalid_blr Invalid request BLR at offset -104 335544390 syntaxerr BLR syntax error: expected <string> at offset , encountered -104 335544425 ctxinuse Context already in use (BLR error) release -104 335544743 token_too_long Token size exceeds limit -104 335544763 invalid_string_constant A string constant is delimited by double quotes -104 335544764 transitional_date DATE must be changed

underlying database names do not have to be equal. Vitess will rewrite these calls to use the literal string for the keyspace name. (This also applies to the synonym SCHEMA()) • ROW_COUNT() and FOUND_ROWS() appear in the binlog. API Changes for VStream Copy To use VStream Copy you just need to pass an empty string as the position. The only other change is in the vgtid structure. It now becomes a list of (keyspace achieved by using a database name like mykeyspace:-80@rdonly in your MySQL application client connection string. Features description: Reference documents for Vitess features Messaging Vitess messaging gives

underlying database names do not have to be equal. Vitess will rewrite these calls to use the literal string for the keyspace name. (This also applies to the synonym SCHEMA()) • ROW_COUNT() and FOUND_ROWS() the binlog. 62 API Changes for VStream Copy To use VStream Copy you just need to pass an empty string as the position. The only other change is in the vgtid structure. It now becomes a list of (keyspace irrespective of the data type. However it further requests collation specific information (weight_string) from the underlying MySQL instance. This can be avoided for numeric columns which is discussed further

underlying database names do not have to be equal. Vitess will rewrite these calls to use the literal string for the keyspace name. (This also applies to the synonym SCHEMA()) • ROW_COUNT() and FOUND_ROWS() appear in the binlog. API Changes for VStream Copy To use VStream Copy you just need to pass an empty string as the position. The only other change is in the vgtid structure. It now becomes a list of (keyspace irrespective of the data type. However it further requests collation specific information (weight_string) from the underlying MySQL instance. This can be avoided for numeric columns which is discussed further

40E+38 ~ +3.40E+38。 转换: Doris会自动将FLOAT类型转换成DOUBLE类型。用户可以使用CAST()将其转换成TINYINT, SMALLINT, INT, BIGINT, STRING, TIMESTAMP。 DOUBLE数据类型 DOUBLE数据类型 长度: 长度为8字节的浮点类型。 范围: -1.79E+308 ~ +1.79E+308。 mysql> select Doris不会自动将DOUBLE类型转换成其他类型。用户可以使用CAST()将其转换成TINYINT, SMALLINT, INT, BIGINT, STRING, TIMESTAMP。用户可以使用指数符号来描述DOUBLE 类型，或通过STRING转换获得。 DECIMAL数据类型 DECIMAL数据类型 DECIMAL[M, D] 保证精度的小数类型。M代表一共有多少个有效数字，D代表小数点后最多有多少数字。M的范围是[1 语法： 数据类型：通常expression的计算结果都是数字类型，该操作符也支持其他数据类型。如果必须要确保下界和上界都是可比较 的字符，可以使用cast()函数。 使用说明：如果操作数是string类型时使用时，应该小心些。起始部分为上界的长字符串将不会匹配上界，该字符串比上界要 大。between 'A' and 'M'不会匹配‘MJ’。如果需要确保表达式能够正常work，可以使用一些函数，如upper()

underlying database names do not have to be equal. Vitess will rewrite these calls to use the literal string for the keyspace name. (This also applies to the synonym SCHEMA()) • ROW_COUNT() and FOUND_ROWS() appear in the binlog. API Changes for VStream Copy To use VStream Copy you just need to pass an empty string as the position. The only other change is in the vgtid structure. It now becomes a list of (keyspace irrespective of the data type. However it further requests collation specific information (weight_string) from the underlying MySQL instance. This can be avoided for numeric columns which is discussed further

public class Student { private int id; private String name; private String branch; private int percentage; private int phone; private String email; //Setters and getters } Mapped private String name; private String branch; private int percentage; private int phone; private String email; public Student(String name, String branch, int percentage, int phone, String email) Here, parameteType − could take a value as string, int, float, double, or any class object based on requirement. In this example, we would pass Student

achieved by using a database name like mykeyspace:-80@rdonly in your MySQL application client connection string. MySQL Replication {{< warning >}} Vitess requires the use of Row-Based Replication with GTIDs ApplyVSchema command applies the specified VSchema to the keyspace. The VSchema can be specified as a string or in a file. RebuildVSchemaGraph The RebuildVSchemaGraph command propagates the global VSchema values are strictly lower than it. Vitess always converts sharding keys to a left-justified binary string for computing a shard. This left-justification makes the right-most zeroes insignificant and optional