1、不加索引查询的SQL：SELECT SQL_NO_CACHE * FROM string_index_test WHERE name=‘forlan’;Benchmark Average number of seconds to run all queries: 8.328 seconds Minimum number of seconds to run all queries: 8.328 seconds Maximum number of seconds to run all queries: 8.328 seconds...
total processors:32,aio thread pool size:64 each process allocated socket buffer pool bytes ,a page size:2097152 a page's chunk number(PageSize/ChunkSize) is:512 buffer page's number is:6402018-06-29 14:53:02.257 INFO [Wrapper...
HOSTEVENT_NAMECOUNT_ALLOCCOUNT_FREESUM_NUMBER_OF_BYTES_ALLOCSUM_NUMBER_OF_BYTES_FREELOW_COUNT_USEDCURRENT_COUNT_USEDHIGH_COUNT_USEDLOW_NUMBER_OF_BYTES_USEDCURRENT_NUMBER_OF_BYTES_USEDHIGH_NUMBER_OF_BYTES_USEDlocalhost memory/sql/Owned_gtids::to_string0000000000localhost memory/sql/Log_event000000000...
DATETIME无小数秒部分: 代码语言:shell AI代码解释 1bit sign(1=non-negative,0=negative)17bits year*13+month(year0-9999, month0-12)5bits day(0-31)5bits hour(0-23)6bits minute(0-59)6bits second(0-59)---40bits=5bytes sign一直是1,值0保留。 小数秒部分存储如下: 2. 常见用法 了解了五...
(columnName);InputStreaminputStream=blob.getBinaryStream();ByteArrayOutputStreamoutputStream=newByteArrayOutputStream();byte[]buffer=newbyte[4096];intbytesRead=-1;while((bytesRead=inputStream.read(buffer))!=-1){outputStream.write(buffer,0,bytesRead);}returnnewString(outputStream.toByteArray());}...
3.时区转化 ,存储时对当前的时区进行转换,检索时再转换回当前的时区。 datetime 1.8个字节储存(8 bytes storage) 2.实际格式储存(Just stores what you have stored and retrieves the same thing which you have stored.) 3.与时区无关(It has nothing to deal with the TIMEZONE and Conversion.)...
2.String ——>Date 2.1使用的函数:STR_TO_DATE(str,format) str:字符形式的日期 format:格式化样式 eg: STR_TO_DATE('1992-04-12',"%Y-%m-%d") 输出:1992-04-12(日期形式) 2.2直接用date(20170101)格式 eg:start_time BETWEEN date(20170603) AND date(20170604) ...
其中内置group_concat返回一个聚合的string,最大长度由参数group_concat_max_len(Maximum allowed result length in bytes for the GROUP_CONCAT())决定,默认是1024,一般都太短了,开发要求改长一点,例如1024000。 当group_concat返回的结果集的大小超过max_allowed_packet限制的时候,程序会报错,这一点要额外注意。
STRING TEXT MEDIUMTEXT LONGTEXT TINYBLOB BYTES 重要 Flink仅支持小于等于2,147,483,647(2^31 - 1)的MySQL BLOB类型的记录。 BLOB MEDIUMBLOB LONGBLOB 数据摄入 MySQL连接器作为数据源可以在数据摄入YAML作业中使用。 语法结构 source: type: mysql name: MySQL Source hostname: localhost port: 3306 username...
STRING TEXT MEDIUMTEXT LONGTEXT TINYBLOB BYTES 重要 Flink仅支持小于等于2,147,483,647(2^31 - 1)的MySQL BLOB类型的记录。 BLOB MEDIUMBLOB LONGBLOB 数据摄入 MySQL连接器作为数据源可以在数据摄入YAML作业中使用。 语法结构 source: type: mysql name: MySQL Source hostname: localhost port: 3306 username...