腾讯云TDSQL MySQL版 - 开发指南兼容性

语言结构分布式实例支持所有 MySQL 使用的文字格式，包括：

String Literals Numeric Literals Date and Time Literals Hexadecimal Literals Bit-Value Literals Boolean Literals NULL Values String Literals String Literals 是一个 bytes 或者 characters 的序列，两端被单引号'或者双引号"包围，TDSQL MySQL版目前不支持 ANSI_QUOTES SQL MODE，双引号"包围的始终认为是 String Literals，而不是 identifier。

不支持 character set introducer，即[_charset_name]'string' [COLLATE collation_name]这种格式。

支持的转义字符：

\0: ASCII NUL (X’00’) 字符 \‘: 单引号 \“: 双引号 \b: 退格符号 \n: 换行符 \r: 回车符 \t: tab 符（制表符） \z: ASCII 26 (Ctrl + Z) \: 反斜杠
%: % _: _ Numeric Literals 数值字面值包括 integer、Decimal 类型、浮点数字面值。 integer 可以包括.作为小数点分隔，数字前可以有-或者+来表示正数或者负数。精确数值字面值可以表示为如下格式：1, .2, 3.4, -5, -6.78, +9.10。科学记数法，如下格式：1.2E3, 1.2E-3, -1.2E3, -1.2E-3。

Date and Time Literals DATE 支持如下格式：

'YYYY-MM-DD' or 'YY-MM-DD' 'YYYYMMDD' or 'YYMMDD' YYYYMMDD or YYMMDD 如：'2012-12-31', '2012/12/31', '2012^12^31', '2012@12@31' '20070523' , '070523' DATETIME，TIMESTAMP 支持如下格式：

'YYYY-MM-DD HH:MM:SS' or 'YY-MM-DD HH:MM:SS' 'YYYYMMDDHHMMSS' or 'YYMMDDHHMMSS' YYYYMMDDHHMMSS or YYMMDDHHMMSS 如'2012-12-31 11:30:45', '2012^12^31 11+30+45', '2012/12/31 113045', '2012@12@31 11^30^45'，19830905132800 Hexadecimal Literals 支持格式如下：

X'01AF' X'01af' x'01AF' x'01af' 0x01AF 0x01af Bit-Value Literals 支持格式如下：

b'01' B'01' 0b01 Boolean Literals 常量 TRUE 和 FALSE 等于1和0，大小写不敏感。

mysql> SELECT TRUE, true, FALSE, false; +------+------+-------+-------+ | TRUE | TRUE | FALSE | FALSE | +------+------+-------+-------+ | 1 | 1 | 0 | 0 | +------+------+-------+-------+ 1 row in set (0.03 sec) NULL Values NULL 代表数据为空，大小写不敏感，与 \N（大小写敏感）同义。需要注意的是 NULL 跟0并不一样，跟空字符串''也不一样。

字符集和时区支持 MySQL 的所有字符集和字符序：

支持通过设置 time_zone 变量修改时区相关的属性：

mysql> show variables like '%time_zone%'; +------------------+--------+ | Variable_name | Value | +------------------+--------+ | system_time_zone | CST | | time_zone | SYSTEM | +------------------+--------+ 2 rows in set (0.00 sec) mysql> create table test.tt (ts timestamp, dt datetime,c int) shardkey=c; Query OK, 0 rows affected (0.49 sec) mysql> insert into test.tt (ts,dt,c)values ('2017-10-01 12:12:12', '2017-10-01 12:12:12',1); Query OK, 1 row affected (0.09 sec) mysql> select * from test.tt; +---------------------+---------------------+------+ | ts | dt | c | +---------------------+---------------------+------+ | 2017-10-01 12:12:12 | 2017-10-01 12:12:12 | 1 | +---------------------+---------------------+------+ 1 row in set (0.04 sec) mysql> set time_zone = '+12:00'; Query OK, 0 rows affected (0.00 sec) mysql> show variables like '%time_zone%'; +------------------+--------+ | Variable_name | Value | +------------------+--------+ | system_time_zone | CST | | time_zone | +12:00 | +------------------+--------+ 2 rows in set (0.00 sec) mysql> select * from test.tt; +---------------------+---------------------+------+ | ts | dt | c | +---------------------+---------------------+------+ | 2017-10-01 16:12:12 | 2017-10-01 12:12:12 | 1 | +---------------------+---------------------+------+ 1 row in set (0.06 sec) 数据类型支持 MySQL 的所有数据类型，包括数字，字符，日期，空间类型，JSON。

数字整型支持 INTEGER， INT，SMALLINT，TINYINT，MEDIUMINT，BIGINT

类型字节数最小值（有符号/无符号）最大值（有符号/无符号） TINYINT 1 -128/0 127/255 SMALLINT 2 -32768/0 32767/65535 MEDIUMINT 3 -8388608/0 8388607/16777215 INT 4 -2147483648/0 2147483647/4294967295 BIGINT 8 -9223372036854775808/0 9223372036854775807/18446744073709551615 浮点类型支持 FLOAT 和 DOUBLE，格式 FLOAT(M,D) 、REAL(M,D) 或 DOUBLE PRECISION(M,D)

定点类型支持 DECIMAL和NUMERIC，格式 DECIMAL(M,D)

字符支持如下字符类型：

CHAR 和 VARCHAR Types BINARY 和 VARBINARY Types BLOB 和 TEXT Types TINYBLOB，TINYTEXT，MEDIUMBLOB,MEDIUMTEXT，LONGBLOB，LONGTEXT ENUM Type SET Type 日期支持如下时间类型：

DATE, DATETIME, TIMESTAMP Types TIME Type YEAR Type 空间支持如下空间类型：

GEOMETRY POINT LINESTRING POLYGON MULTIPOINT MULTILINESTRING MULTIPOLYGON GEOMETRYCOLLECTION JSON 支持存储 JSON 格式的数据，使得对 JSON 处理更加有效，同时又能提早检查错误：

注意：对 JSON 类型的字段进行排序时，不支持混合类型排序。如不能将 string 类型和 int 类型做比较，同类型排序只支持数值类型，string 类型，其它类型排序不处理。对下表来说，不支持select * from t1 order by t1->"$.key2"，因为排序列中包含了数值和字符串类型。

mysql> CREATE TABLE t1 (jdoc JSON,a int) shardkey=a; Query OK, 0 rows affected (0.30 sec) mysql> INSERT INTO t1 (jdoc,a)VALUES('{"key1": "value1", "key2": "value2"}',1); Query OK, 1 row affected (0.00 sec) mysql> INSERT INTO t1 (jdoc,a)VALUES('{"key1": "value1", "key2": 2}',2); mysql> INSERT INTO t1 (jdoc,a)VALUES('[1, 2,',5); ERROR 3140 (22032): Invalid JSON text: "Invalid value." at position 6 in value for column 't1.jdoc'. mysql> select * from t1; +--------------------------------------+---+ | jdoc | a | +--------------------------------------+---+ | {"key1": "value1", "key2": "value2"} | 1 | | {"key1": "value1", "key2": 2} | 2 | +--------------------------------------+---+ 2 rows in set (0.00 sec) 函数支持 Control Flow Functions

Name Description CASE Case operator IF() If/else construct IFNULL() Null if/else construct NULLIF() Return NULL if expr1 = expr2 String Functions

Name Description ASCII() Return numeric value of left-most character BIN() Return a string containing binary representation of a number BIT_LENGTH() Return length of argument in bits CHAR() Return the character for each integer passed CHAR_LENGTH() Return number of characters in argument CHARACTER_LENGTH() Synonym for CHAR_LENGTH() CONCAT() Return concatenated string CONCAT_WS() Return concatenate with separator ELT() Return string at index number EXPORT_SET() Return a string such that for every bit set in the value bits, you get an on string and for every unset bit, you get an off string FIELD() Return the index (position) of the first argument in the subsequent arguments FIND_IN_SET() Return the index position of the first argument within the second argument FORMAT() Return a number formatted to specified number of decimal places FROM_BASE64() Decode to a base-64 string and return result HEX() Return a hexadecimal representation of a decimal or string value INSERT() Insert a substring at the specified position up to the specified number of characters INSTR() Return the index of the first occurrence of substring LCASE() Synonym for LOWER() LEFT() Return the leftmost number of characters as specified LENGTH() Return the length of a string in bytes LIKE Simple pattern matching LOAD_FILE() Load the named file LOCATE() Return the position of the first occurrence of substring LOWER() Return the argument in lowercase LPAD() Return the string argument, left-padded with the specified string LTRIM() Remove leading spaces MAKE_SET() Return a set of comma-separated strings that have the corresponding bit in bits set MATCH Perform full-text search MID() Return a substring starting from the specified position NOT LIKE Negation of simple pattern matching NOT REGEXP Negation of REGEXP OCT() Return a string containing octal representation of a number OCTET_LENGTH() Synonym for LENGTH() ORD() Return character code for leftmost character of the argument POSITION() Synonym for LOCATE() QUOTE() Escape the argument for use in an SQL statement REGEXP Pattern matching using regular expressions REPEAT() Repeat a string the specified number of times REPLACE() Replace occurrences of a specified string REVERSE() Reverse the characters in a string RIGHT() Return the specified rightmost number of characters RLIKE Synonym for REGEXP RPAD() Append string the specified number of times RTRIM() Remove trailing spaces SOUNDEX() Return a soundex string SOUNDS LIKE Compare sounds SPACE() Return a string of the specified number of spaces STRCMP() Compare two strings SUBSTR() Return the substring as specified SUBSTRING() Return the substring as specified SUBSTRING_INDEX() Return a substring from a string before the specified number of occurrences of the delimiter TO_BASE64() Return the argument converted to a base-64 string TRIM() Remove leading and trailing spaces UCASE() Synonym for UPPER() UNHEX() Return a string containing hex representation of a number UPPER() Convert to uppercase WEIGHT_STRING() Return the weight string for a string Numeric Functions and Operators

Name Description ABS() Return the absolute value ACOS() Return the arc cosine ASIN() Return the arc sine ATAN() Return the arc tangent ATAN2(), ATAN() Return the arc tangent of the two arguments CEIL() Return the smallest integer value not less than the argument CEILING() Return the smallest integer value not less than the argument CONV() Convert numbers between different number bases COS() Return the cosine COT() Return the cotangent CRC32() Compute a cyclic redundancy check value DEGREES() Convert radians to degrees DIV Integer division / Division operator EXP() Raise to the power of FLOOR() Return the largest integer value not greater than the argument LN() Return the natural logarithm of the argument LOG() Return the natural logarithm of the first argument LOG10() Return the base-10 logarithm of the argument LOG2() Return the base-2 logarithm of the argument

Minus operator MOD() Return the remainder %, MOD Modulo operator PI() Return the value of pi
Addition operator POW() Return the argument raised to the specified power POWER() Return the argument raised to the specified power RADIANS() Return argument converted to radians RAND() Return a random floating-point value ROUND() Round the argument SIGN() Return the sign of the argument SIN() Return the sine of the argument SQRT() Return the square root of the argument TAN() Return the tangent of the argument
Multiplication operator TRUNCATE() Truncate to specified number of decimal places
Change the sign of the argument Date and Time Functions

Name Description ADDDATE() Add time values (intervals) to a date value ADDTIME() Add time CONVERT_TZ() Convert from one time zone to another CURDATE() Return the current date CURRENT_DATE(), CURRENT_DATE Synonyms for CURDATE() CURRENT_TIME(), CURRENT_TIME Synonyms for CURTIME() CURRENT_TIMESTAMP(), CURRENT_TIMESTAMP Synonyms for NOW() CURTIME() Return the current time DATE() Extract the date part of a date or datetime expression DATE_ADD() Add time values (intervals) to a date value DATE_FORMAT() Format date as specified DATE_SUB() Subtract a time value (interval) from a date DATEDIFF() Subtract two dates DAY() Synonym for DAYOFMONTH() DAYNAME() Return the name of the weekday DAYOFMONTH() Return the day of the month (0-31) DAYOFWEEK() Return the weekday index of the argument DAYOFYEAR() Return the day of the year (1-366) EXTRACT() Extract part of a date FROM_DAYS() Convert a day number to a date FROM_UNIXTIME() Format Unix timestamp as a date GET_FORMAT() Return a date format string HOUR() Extract the hour LAST_DAY Return the last day of the month for the argument LOCALTIME(), LOCALTIME Synonym for NOW() LOCALTIMESTAMP, LOCALTIMESTAMP() Synonym for NOW() MAKEDATE() Create a date from the year and day of year MAKETIME() Create time from hour, minute, second MICROSECOND() Return the microseconds from argument MINUTE() Return the minute from the argument MONTH() Return the month from the date passed MONTHNAME() Return the name of the month NOW() Return the current date and time PERIOD_ADD() Add a period to a year-month PERIOD_DIFF() Return the number of months between periods QUARTER() Return the quarter from a date argument SEC_TO_TIME() Converts seconds to 'HH:MM:SS' format SECOND() Return the second (0-59) STR_TO_DATE() Convert a string to a date SUBDATE() Synonym for DATE_SUB() when invoked with three arguments SUBTIME() Subtract times SYSDATE() Return the time at which the function executes TIME() Extract the time portion of the expression passed TIME_FORMAT() Format as time TIME_TO_SEC() Return the argument converted to seconds TIMEDIFF() Subtract time TIMESTAMP() With a single argument, this function returns the date or datetime expression; with two arguments, the sum of the arguments TIMESTAMPADD() Add an interval to a datetime expression TIMESTAMPDIFF() Subtract an interval from a datetime expression TO_DAYS() Return the date argument converted to days TO_SECONDS() Return the date or datetime argument converted to seconds since Year 0 UNIX_TIMESTAMP() Return a Unix timestamp UTC_DATE() Return the current UTC date UTC_TIME() Return the current UTC time UTC_TIMESTAMP() Return the current UTC date and time WEEK() Return the week number WEEKDAY() Return the weekday index WEEKOFYEAR() Return the calendar week of the date (1-53) YEAR() Return the year YEARWEEK() Return the year and week Aggregate (GROUP BY) Functions

Name Description AVG() Return the average value of the argument COUNT() Return a count of the number of rows returned MAX() Return the maximum value MIN() Return the minimum value SUM() Return the sum Bit Functions and Operators

Name Description BIT_COUNT() Return the number of bits that are set & Bitwise AND ~ Bitwise inversion | Bitwise OR ^ Bitwise XOR << Left shift

Right shift Cast Functions and Operators

Name Description BINARY Cast a string to a binary string CAST() Cast a value as a certain type CONVERT() Cast a value as a certain type

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原文链接：https://blog.csdn.net/weixin_43872058/article/details/119791834