Name Description
ABS() Return the absolute value
ACOS() Return the arc cosine
ADDDATE() Add time values (intervals) to a date value
ADDTIME() Add time
AES_DECRYPT() Decrypt using AES
AES_ENCRYPT() Encrypt using AES
AND&& Logical AND
ANY_VALUE() Suppress ONLY_FULL_GROUP_BY value rejection
Area() (deprecated 5.7.6) Return Polygon or MultiPolygon area
AsBinary()AsWKB() (deprecated 5.7.6) Convert from internal geometry format to WKB
ASCII() Return numeric value of left-most character
ASIN() Return the arc sine
= Assign a value (as part of a SET statement, or as part of the SET clause in anUPDATE statement)
:= Assign a value
AsText()AsWKT() (deprecated 5.7.6) Convert from internal geometry format to WKT
ASYMMETRIC_DECRYPT() Decrypt ciphertext using private or public key
ASYMMETRIC_DERIVE() Derive symmetric key from asymmetric keys
ASYMMETRIC_ENCRYPT() Encrypt cleartext using private or public key
ASYMMETRIC_SIGN() Generate signature from digest
ASYMMETRIC_VERIFY() Verify that signature matches digest
ATAN() Return the arc tangent
ATAN2()ATAN() Return the arc tangent of the two arguments
AVG() Return the average value of the argument
BENCHMARK() Repeatedly execute an expression
BETWEEN ... AND ... Check whether a value is within a range of values
BIN() Return a string containing binary representation of a number
BINARY Cast a string to a binary string
BIT_AND() Return bitwise AND
BIT_COUNT() Return the number of bits that are set
BIT_LENGTH() Return length of argument in bits
BIT_OR() Return bitwise OR
BIT_XOR() Return bitwise XOR
& Bitwise AND
~ Bitwise inversion
| Bitwise OR
^ Bitwise XOR
Buffer() (deprecated 5.7.6) Return geometry of points within given distance from geometry
CASE Case operator
CAST() Cast a value as a certain type
CEIL() Return the smallest integer value not less than the argument
CEILING() Return the smallest integer value not less than the argument
Centroid() (deprecated 5.7.6) Return centroid as a point
CHAR() Return the character for each integer passed
CHAR_LENGTH() Return number of characters in argument
CHARACTER_LENGTH() Synonym for CHAR_LENGTH()
CHARSET() Return the character set of the argument
COALESCE() Return the first non-NULL argument
COERCIBILITY() Return the collation coercibility value of the string argument
COLLATION() Return the collation of the string argument
COMPRESS() Return result as a binary string
CONCAT() Return concatenated string
CONCAT_WS() Return concatenate with separator
CONNECTION_ID() Return the connection ID (thread ID) for the connection
Contains() (deprecated 5.7.6) Whether MBR of one geometry contains MBR of another
CONV() Convert numbers between different number bases
CONVERT() Cast a value as a certain type
CONVERT_TZ() Convert from one time zone to another
ConvexHull() (deprecated 5.7.6) Return convex hull of geometry
COS() Return the cosine
COT() Return the cotangent
COUNT() Return a count of the number of rows returned
COUNT(DISTINCT) Return the count of a number of different values
CRC32() Compute a cyclic redundancy check value
CREATE_ASYMMETRIC_PRIV_KEY() Create private key
CREATE_ASYMMETRIC_PUB_KEY() Create public key
CREATE_DH_PARAMETERS() Generate shared DH secret
CREATE_DIGEST() Generate digest from string
Crosses() (deprecated 5.7.6) Whether one geometry crosses 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()
CURRENT_USER()CURRENT_USER The authenticated user name and host name
CURTIME() Return the current time
DATABASE() Return the default (current) database name
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)
DECODE() (deprecated 5.7.2) Decodes a string encrypted using ENCODE()
DEFAULT() Return the default value for a table column
DEGREES() Convert radians to degrees
DES_DECRYPT() (deprecated 5.7.6) Decrypt a string
DES_ENCRYPT() (deprecated 5.7.6) Encrypt a string
Dimension() (deprecated 5.7.6) Dimension of geometry
Disjoint() (deprecated 5.7.6) Whether MBRs of two geometries are disjoint
Distance() (deprecated 5.7.6) The distance of one geometry from another
DIV Integer division
/ Division operator
ELT() Return string at index number
ENCODE() (deprecated 5.7.2) Encode a string
ENCRYPT() (deprecated 5.7.6) Encrypt a string
EndPoint() (deprecated 5.7.6) End Point of LineString
Envelope() (deprecated 5.7.6) Return MBR of geometry
= Equal operator
<=> NULL-safe equal to operator
Equals() (deprecated 5.7.6) Whether MBRs of two geometries are equal
EXP() Raise to the power of
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
ExteriorRing() (deprecated 5.7.6) Return exterior ring of Polygon
EXTRACT() Extract part of a date
ExtractValue() Extracts a value from an XML string using XPath notation
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
FLOOR() Return the largest integer value not greater than the argument
FORMAT() Return a number formatted to specified number of decimal places
FOUND_ROWS() For a SELECT with a LIMIT clause, the number of rows that would be returned were there no LIMIT clause
FROM_BASE64() Decode to a base-64 string and return result
FROM_DAYS() Convert a day number to a date
FROM_UNIXTIME() Format Unix timestamp as a date
GeomCollFromText()GeometryCollectionFromText() (deprecated 5.7.6) Return geometry collection from WKT
GeomCollFromWKB()GeometryCollectionFromWKB() (deprecated 5.7.6) Return geometry collection from WKB
GeometryCollection() Construct geometry collection from geometries
GeometryN() (deprecated 5.7.6) Return N-th geometry from geometry collection
GeometryType() (deprecated 5.7.6) Return name of geometry type
GeomFromText()GeometryFromText()(deprecated 5.7.6) Return geometry from WKT
GeomFromWKB()GeometryFromWKB() (deprecated 5.7.6) Return geometry from WKB
GET_FORMAT() Return a date format string
GET_LOCK() Get a named lock
GLength() (deprecated 5.7.6) Return length of LineString
> Greater than operator
>= Greater than or equal operator
GREATEST() Return the largest argument
GROUP_CONCAT() Return a concatenated string
GTID_SUBSET() Return true if all GTIDs in subset are also in set; otherwise false.
GTID_SUBTRACT() Return all GTIDs in set that are not in subset.
HEX() Return a hexadecimal representation of a decimal or string value
HOUR() Extract the hour
IF() If/else construct
IFNULL() Null if/else construct
IN() Check whether a value is within a set of values
INET_ATON() Return the numeric value of an IP address
INET_NTOA() Return the IP address from a numeric value
INET6_ATON() Return the numeric value of an IPv6 address
INET6_NTOA() Return the IPv6 address from a numeric 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
InteriorRingN() (deprecated 5.7.6) Return N-th interior ring of Polygon
Intersects() (deprecated 5.7.6) Whether MBRs of two geometries intersect
INTERVAL() Return the index of the argument that is less than the first argument
IS Test a value against a boolean
IS_FREE_LOCK() Whether the named lock is free
IS_IPV4() Whether argument is an IPv4 address
IS_IPV4_COMPAT() Whether argument is an IPv4-compatible address
IS_IPV4_MAPPED() Whether argument is an IPv4-mapped address
IS_IPV6() Whether argument is an IPv6 address
IS NOT Test a value against a boolean
IS NOT NULL NOT NULL value test
IS NULL NULL value test
IS_USED_LOCK() Whether the named lock is in use; return connection identifier if true
IsClosed() (deprecated 5.7.6) Whether a geometry is closed and simple
IsEmpty() (deprecated 5.7.6) Placeholder function
ISNULL() Test whether the argument is NULL
IsSimple() (deprecated 5.7.6) Whether a geometry is simple
JSON_APPEND() (deprecated 5.7.9) Append data to JSON document
JSON_ARRAY() Create JSON array
JSON_ARRAY_APPEND() Append data to JSON document
JSON_ARRAY_INSERT() Insert into JSON array
JSON_ARRAYAGG() Return result set as a single JSON array
-> Return value from JSON column after evaluating path; equivalent to JSON_EXTRACT().
JSON_CONTAINS() Whether JSON document contains specific object at path
JSON_CONTAINS_PATH() Whether JSON document contains any data at path
JSON_DEPTH() Maximum depth of JSON document
JSON_EXTRACT() Return data from JSON document
->> Return value from JSON column after evaluating path and unquoting the result; equivalent to JSON_UNQUOTE(JSON_EXTRACT()).
JSON_INSERT() Insert data into JSON document
JSON_KEYS() Array of keys from JSON document
JSON_LENGTH() Number of elements in JSON document
JSON_MERGE() (deprecated 5.7.22) Merge JSON documents, preserving duplicate keys. Deprecated synonym for JSON_MERGE_PRESERVE()
JSON_MERGE_PATCH() Merge JSON documents, replacing values of duplicate keys
JSON_MERGE_PRESERVE() Merge JSON documents, preserving duplicate keys
JSON_OBJECT() Create JSON object
JSON_OBJECTAGG() Return result set as a single JSON object
JSON_PRETTY() Prints a JSON document in human-readable format, with each array element or object member printed on a new line, indented two spaces with respect to its parent.
JSON_QUOTE() Quote JSON document
JSON_REMOVE() Remove data from JSON document
JSON_REPLACE() Replace values in JSON document
JSON_SEARCH() Path to value within JSON document
JSON_SET() Insert data into JSON document
JSON_STORAGE_SIZE() Space used for storage of binary representation of a JSON document; for a JSON column, the space used when the document was inserted, prior to any partial updates
JSON_TYPE() Type of JSON value
JSON_UNQUOTE() Unquote JSON value
JSON_VALID() Whether JSON value is valid
LAST_DAY Return the last day of the month for the argument
LAST_INSERT_ID() Value of the AUTOINCREMENT column for the last INSERT
LCASE() Synonym for LOWER()
LEAST() Return the smallest argument
LEFT() Return the leftmost number of characters as specified
<< Left shift
LENGTH() Return the length of a string in bytes
< Less than operator
<= Less than or equal operator
LIKE Simple pattern matching
LineFromText()LineStringFromText()(deprecated 5.7.6) Construct LineString from WKT
LineFromWKB()LineStringFromWKB()(deprecated 5.7.6) Construct LineString from WKB
LineString() Construct LineString from Point values
LN() Return the natural logarithm of the argument
LOAD_FILE() Load the named file
LOCALTIME()LOCALTIME Synonym for NOW()
LOCALTIMESTAMPLOCALTIMESTAMP() Synonym for NOW()
LOCATE() Return the position of the first occurrence of substring
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
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
MAKEDATE() Create a date from the year and day of year
MAKETIME() Create time from hour, minute, second
MASTER_POS_WAIT() Block until the slave has read and applied all updates up to the specified position
MATCH Perform full-text search
MAX() Return the maximum value
MBRContains() Whether MBR of one geometry contains MBR of another
MBRCoveredBy() Whether one MBR is covered by another
MBRCovers() Whether one MBR covers another
MBRDisjoint() Whether MBRs of two geometries are disjoint
MBREqual() (deprecated 5.7.6) Whether MBRs of two geometries are equal
MBREquals() Whether MBRs of two geometries are equal
MBRIntersects() Whether MBRs of two geometries intersect
MBROverlaps() Whether MBRs of two geometries overlap
MBRTouches() Whether MBRs of two geometries touch
MBRWithin() Whether MBR of one geometry is within MBR of another
MD5() Calculate MD5 checksum
MICROSECOND() Return the microseconds from argument
MID() Return a substring starting from the specified position
MIN() Return the minimum value
- Minus operator
MINUTE() Return the minute from the argument
MLineFromText()MultiLineStringFromText()(deprecated 5.7.6) Construct MultiLineString from WKT
MLineFromWKB()MultiLineStringFromWKB()(deprecated 5.7.6) Construct MultiLineString from WKB
MOD() Return the remainder
%MOD Modulo operator
MONTH() Return the month from the date passed
MONTHNAME() Return the name of the month
MPointFromText()MultiPointFromText()(deprecated 5.7.6) Construct MultiPoint from WKT
MPointFromWKB()MultiPointFromWKB()(deprecated 5.7.6) Construct MultiPoint from WKB
MPolyFromText()MultiPolygonFromText()(deprecated 5.7.6) Construct MultiPolygon from WKT
MPolyFromWKB()MultiPolygonFromWKB()(deprecated 5.7.6) Construct MultiPolygon from WKB
MultiLineString() Contruct MultiLineString from LineString values
MultiPoint() Construct MultiPoint from Point values
MultiPolygon() Construct MultiPolygon from Polygon values
NAME_CONST() Causes the column to have the given name
NOT! Negates value
NOT BETWEEN ... AND ... Check whether a value is not within a range of values
!=<> Not equal operator
NOT IN() Check whether a value is not within a set of values
NOT LIKE Negation of simple pattern matching
NOT REGEXP Negation of REGEXP
NOW() Return the current date and time
NULLIF() Return NULL if expr1 = expr2
NumGeometries() (deprecated 5.7.6) Return number of geometries in geometry collection
NumInteriorRings() (deprecated 5.7.6) Return number of interior rings in Polygon
NumPoints() (deprecated 5.7.6) Return number of points in LineString
OCT() Return a string containing octal representation of a number
OCTET_LENGTH() Synonym for LENGTH()
OLD_PASSWORD() Return the value of the pre-4.1 implementation of PASSWORD
||OR Logical OR
ORD() Return character code for leftmost character of the argument
Overlaps() (deprecated 5.7.6) Whether MBRs of two geometries overlap
PASSWORD() (deprecated 5.7.6) Calculate and return a password string
PERIOD_ADD() Add a period to a year-month
PERIOD_DIFF() Return the number of months between periods
PI() Return the value of pi
+ Addition operator
Point() Construct Point from coordinates
PointFromText() (deprecated 5.7.6) Construct Point from WKT
PointFromWKB() (deprecated 5.7.6) Construct Point from WKB
PointN() (deprecated 5.7.6) Return N-th point from LineString
PolyFromText()PolygonFromText() (deprecated 5.7.6) Construct Polygon from WKT
PolyFromWKB()PolygonFromWKB() (deprecated 5.7.6) Construct Polygon from WKB
Polygon() Construct Polygon from LineString arguments
POSITION() Synonym for LOCATE()
POW() Return the argument raised to the specified power
POWER() Return the argument raised to the specified power
PROCEDURE ANALYSE() (deprecated 5.7.18) Analyze the results of a query
QUARTER() Return the quarter from a date argument
QUOTE() Escape the argument for use in an SQL statement
RADIANS() Return argument converted to radians
RAND() Return a random floating-point value
RANDOM_BYTES() Return a random byte vector
REGEXP Whether string matches regular expression
RELEASE_ALL_LOCKS() Releases all current named locks
RELEASE_LOCK() Releases the named lock
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
>> Right shift
RLIKE Whether string matches regular expression
ROUND() Round the argument
ROW_COUNT() The number of rows updated
RPAD() Append string the specified number of times
RTRIM() Remove trailing spaces
SCHEMA() Synonym for DATABASE()
SEC_TO_TIME() Converts seconds to 'HH:MM:SS' format
SECOND() Return the second (0-59)
SESSION_USER() Synonym for USER()
SHA1()SHA() Calculate an SHA-1 160-bit checksum
SHA2() Calculate an SHA-2 checksum
SIGN() Return the sign of the argument
SIN() Return the sine of the argument
SLEEP() Sleep for a number of seconds
SOUNDEX() Return a soundex string
SOUNDS LIKE Compare sounds
SPACE() Return a string of the specified number of spaces
SQRT() Return the square root of the argument
SRID() (deprecated 5.7.6) Return spatial reference system ID for geometry
ST_Area() Return Polygon or MultiPolygon area
ST_AsBinary()ST_AsWKB() Convert from internal geometry format to WKB
ST_AsGeoJSON() Generate GeoJSON object from geometry
ST_AsText()ST_AsWKT() Convert from internal geometry format to WKT
ST_Buffer() Return geometry of points within given distance from geometry
ST_Buffer_Strategy() Produce strategy option for ST_Buffer()
ST_Centroid() Return centroid as a point
ST_Contains() Whether one geometry contains another
ST_ConvexHull() Return convex hull of geometry
ST_Crosses() Whether one geometry crosses another
ST_Difference() Return point set difference of two geometries
ST_Dimension() Dimension of geometry
ST_Disjoint() Whether one geometry is disjoint from another
ST_Distance() The distance of one geometry from another
ST_Distance_Sphere() Minimum distance on earth between two geometries
ST_EndPoint() End Point of LineString
ST_Envelope() Return MBR of geometry
ST_Equals() Whether one geometry is equal to another
ST_ExteriorRing() Return exterior ring of Polygon
ST_GeoHash() Produce a geohash value
ST_GeomCollFromText()ST_GeometryCollectionFromText()ST_GeomCollFromTxt() Return geometry collection from WKT
ST_GeomCollFromWKB()ST_GeometryCollectionFromWKB() Return geometry collection from WKB
ST_GeometryN() Return N-th geometry from geometry collection
ST_GeometryType() Return name of geometry type
ST_GeomFromGeoJSON() Generate geometry from GeoJSON object
ST_GeomFromText()ST_GeometryFromText() Return geometry from WKT
ST_GeomFromWKB()ST_GeometryFromWKB() Return geometry from WKB
ST_InteriorRingN() Return N-th interior ring of Polygon
ST_Intersection() Return point set intersection of two geometries
ST_Intersects() Whether one geometry intersects another
ST_IsClosed() Whether a geometry is closed and simple
ST_IsEmpty() Placeholder function
ST_IsSimple() Whether a geometry is simple
ST_IsValid() Whether a geometry is valid
ST_LatFromGeoHash() Return latitude from geohash value
ST_Length() Return length of LineString
ST_LineFromText()ST_LineStringFromText() Construct LineString from WKT
ST_LineFromWKB()ST_LineStringFromWKB() Construct LineString from WKB
ST_LongFromGeoHash() Return longitude from geohash value
ST_MakeEnvelope() Rectangle around two points
ST_MLineFromText()ST_MultiLineStringFromText() Construct MultiLineString from WKT
ST_MLineFromWKB()ST_MultiLineStringFromWKB() Construct MultiLineString from WKB
ST_MPointFromText()ST_MultiPointFromText() Construct MultiPoint from WKT
ST_MPointFromWKB()ST_MultiPointFromWKB() Construct MultiPoint from WKB
ST_MPolyFromText()ST_MultiPolygonFromText() Construct MultiPolygon from WKT
ST_MPolyFromWKB()ST_MultiPolygonFromWKB() Construct MultiPolygon from WKB
ST_NumGeometries() Return number of geometries in geometry collection
ST_NumInteriorRing()ST_NumInteriorRings() Return number of interior rings in Polygon
ST_NumPoints() Return number of points in LineString
ST_Overlaps() Whether one geometry overlaps another
ST_PointFromGeoHash() Convert geohash value to POINT value
ST_PointFromText() Construct Point from WKT
ST_PointFromWKB() Construct Point from WKB
ST_PointN() Return N-th point from LineString
ST_PolyFromText()ST_PolygonFromText() Construct Polygon from WKT
ST_PolyFromWKB()ST_PolygonFromWKB() Construct Polygon from WKB
ST_Simplify() Return simplified geometry
ST_SRID() Return spatial reference system ID for geometry
ST_StartPoint() Start Point of LineString
ST_SymDifference() Return point set symmetric difference of two geometries
ST_Touches() Whether one geometry touches another
ST_Union() Return point set union of two geometries
ST_Validate() Return validated geometry
ST_Within() Whether one geometry is within another
ST_X() Return X coordinate of Point
ST_Y() Return Y coordinate of Point
StartPoint() (deprecated 5.7.6) Start Point of LineString
STD() Return the population standard deviation
STDDEV() Return the population standard deviation
STDDEV_POP() Return the population standard deviation
STDDEV_SAMP() Return the sample standard deviation
STR_TO_DATE() Convert a string to a date
STRCMP() Compare two strings
SUBDATE() Synonym for DATE_SUB() when invoked with three arguments
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
SUBTIME() Subtract times
SUM() Return the sum
SYSDATE() Return the time at which the function executes
SYSTEM_USER() Synonym for USER()
TAN() Return the tangent of the argument
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
* Multiplication operator
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_BASE64() Return the argument converted to a base-64 string
TO_DAYS() Return the date argument converted to days
TO_SECONDS() Return the date or datetime argument converted to seconds since Year 0
Touches() (deprecated 5.7.6) Whether one geometry touches another
TRIM() Remove leading and trailing spaces
TRUNCATE() Truncate to specified number of decimal places
UCASE() Synonym for UPPER()
- Change the sign of the argument
UNCOMPRESS() Uncompress a string compressed
UNCOMPRESSED_LENGTH() Return the length of a string before compression
UNHEX() Return a string containing hex representation of a number
UNIX_TIMESTAMP() Return a Unix timestamp
UpdateXML() Return replaced XML fragment
UPPER() Convert to uppercase
USER() The user name and host name provided by the client
UTC_DATE() Return the current UTC date
UTC_TIME() Return the current UTC time
UTC_TIMESTAMP() Return the current UTC date and time
UUID() Return a Universal Unique Identifier (UUID)
UUID_SHORT() Return an integer-valued universal identifier
VALIDATE_PASSWORD_STRENGTH() Determine strength of password
VALUES() Defines the values to be used during an INSERT
VAR_POP() Return the population standard variance
VAR_SAMP() Return the sample variance
VARIANCE() Return the population standard variance
VERSION() Return a string that indicates the MySQL server version
WAIT_FOR_EXECUTED_GTID_SET() Wait until the given GTIDs have executed on slave.
WAIT_UNTIL_SQL_THREAD_AFTER_GTIDS() Wait until the given GTIDs have executed on slave.
WEEK() Return the week number
WEEKDAY() Return the weekday index
WEEKOFYEAR() Return the calendar week of the date (1-53)
WEIGHT_STRING() Return the weight string for a string
Within() (deprecated 5.7.6) Whether MBR of one geometry is within MBR of another
X() (deprecated 5.7.6) Return X coordinate of Point
XOR Logical XOR
Y() (deprecated 5.7.6) Return Y coordinate of Point
YEAR() Return the year
YEARWEEK() Return the year and week

mysql 函数表的更多相关文章

  1. C++ 虚函数表解析

    转载:陈皓 http://blog.csdn.net/haoel 前言 C++中 的虚函数的作用主要是实现了多态的机制.关于多态,简而言之就是用父类型别的指针指向其子类的实例,然后通过父类的指针调用实 ...

  2. C++ 多态、虚函数机制以及虚函数表

    1.非virtual函数,调用规则取决于对象的显式类型.例如 A* a  = new B(); a->display(); 调用的就是A类中定义的display().和对象本体是B无关系. 2. ...

  3. C++迟后联编和虚函数表

    先看一个题目: class Base { public: virtual void Show(int x) { cout << "In Base class, int x = & ...

  4. C++ 知道虚函数表的存在

    今天翻看陈皓大大的博客,直接找关于C++的东东,看到了虚函数表的内容,找一些能看得懂的地方记下笔记. 0 引子 类中存在虚函数,就会存在虚函数表,在vs2015的实现中,它存在于类的头部. 假设有如下 ...

  5. C++虚函数和虚函数表

    前导 在上面的博文中描述了基类中存在虚函数时,基类和派生类中虚函数表的结构. 在派生类也定义了虚函数时,函数表又是怎样的结构呢? 先看下面的示例代码: #include <iostream> ...

  6. C++ Daily 《5》----虚函数表的共享问题

    问题: 包含一个以上虚函数的 class B, 它所定义的 对象是否共用一个虚函数表? 分析: 由于含有虚函数,因此对象内存包含了一个指向虚函数表的指针,但是这个指针指向的是同一个虚函数表吗? 实验如 ...

  7. C++虚函数表

    大家知道虚函数是通过一张虚函数表来实现的.在这个表中,主要是一个类的虚函数的地址表,这张表解决了继承.覆盖的问题,其内容真是反应实际的函数.这样,在有虚函数的类的实例中,这个表分配在了这个实例的内存中 ...

  8. 对C++虚函数、虚函数表的简单理解

    一.虚函数的作用 以一个通用的图形类来了解虚函数的定义,代码如下: #include "stdafx.h" #include <iostream> using name ...

  9. 深入理解C++虚函数表

    虚函数表是C++类中存放虚函数的一张表,理解虚函数表对于理解多态很重要. 本次使用的编译器是VS2013,为了简化操作,不用去操作函数指针,我使用到了VS的CL编译选项来查看类的内存布局. CL使用方 ...

随机推荐

  1. Matalb中英双语手册-年少无知翻译版本

    更新: 20171207: 这是大学期间参加数模翻译的手册 正文: 愚人节快乐,突然发现自己在博客园的一篇文章.摘取如下: MATLAB 语言是一种工程语言,语法很像 VB 和 C,比 R 语言容易学 ...

  2. (转)数据库函数解析JSON字符串

    一.返回单行单列 二.返回表 三.SQL206版本开始支持 SELECT * FROM OPENJSON(@JsonStr)

  3. ADO.NET 三(Command)

    操作数据库需则要用到 Command 类中提供的属性和方法.下面来介绍一下如何使用 Command 类来操作数据表中的数据. Command 类概述 在 System.Data.SqlClient 命 ...

  4. Spring Boot + RabbitMQ 配置参数解释

    最近生产RabbitMQ出了几次问题,所以抽时间整理了一份关于Spring Boot 整合RabbitMQ环境下的配置参数解释,通过官网文档和网上其他朋友一些文章参考归纳整理而得,有错误之处还请指正~ ...

  5. Linux系统内核正式进入5.0版本时代

    知名Linux内核开发人员兼维护人员Greg Kroah-Hartman今天宣布,Linux Kernel 4.20内核分支已经结束并督促用户尽快升级至更新的内核分支. Linux Kernel 4. ...

  6. 页面、 ajax 、mock

    页面1: //html <form action = "" method="post"  name="loginForm"> & ...

  7. FPM-OVP增强实例-银行账户

    本文是基于NWBC银行账户信息进行增强,相关过程如下: 1.定位需要增强的界面 首先登陆SAP-GUI(尽量EN登陆,ZH可能乱码),输入TCODE:NWBC跳转到浏览器界面,新建银行账户: 注意上图 ...

  8. 用java代码实现构造目录树

    怎么用java代码实现上面这样的目录树? 首先创建数据表 每条数据记录自己的id以及父节点的id 然后进入java代码部分: public String directory(String author ...

  9. Linux实验:ssh免密码配置

    [实验目的]    1)了解ssh工具的作用    2)熟悉ssh配置过程    3)理解ssh原理[实验原理]    SSH是目前比较可靠的专为远程登录会话和其他网络服务提供安全的协议.不同主机之间 ...

  10. centos7小命令

    修改时区:timedate [root@centos2 ~]# timedatectl set-timezone Asia/Shanghai 修改语言:localectl [root@centos2 ...