MySQL Functions
MySQL String Functions
| Function | Description | 
|---|---|
| ASCII | Returns the ASCII value for the specific character | 
| CHAR_LENGTH | Returns the length of a string (in characters) | 
| CHARACTER_LENGTH | Returns the length of a string (in characters) | 
| CONCAT | Adds two or more expressions together | 
| CONCAT_WS | Adds two or more expressions together with a separator | 
| FIELD | Returns the index position of a value in a list of values | 
| FIND_IN_SET | Returns the position of a string within a list of strings | 
| FORMAT | Formats a number to a format like “#,###,###.##”, rounded to a specified number of decimal places | 
| INSERT | Inserts a string within a string at the specified position and for a certain number of characters | 
| INSTR | Returns the position of the first occurrence of a string in another string | 
| LCASE | Converts a string to lower-case | 
| LEFT | Extracts a number of characters from a string (starting from left) | 
| LENGTH | Returns the length of a string (in bytes) | 
| LOCATE | Returns the position of the first occurrence of a substring in a string | 
| LOWER | Converts a string to lower-case | 
| LPAD | Left-pads a string with another string, to a certain length | 
| LTRIM | Removes leading spaces from a string | 
| MID | Extracts a substring from a string (starting at any position) | 
| POSITION | Returns the position of the first occurrence of a substring in a string | 
| REPEAT | Repeats a string as many times as specified | 
| REPLACE | Replaces all occurrences of a substring within a string, with a new substring | 
| REVERSE | Reverses a string and returns the result | 
| RIGHT | Extracts a number of characters from a string (starting from right) | 
| RPAD | Right-pads a string with another string, to a certain length | 
| RTRIM | Removes trailing spaces from a string | 
| SPACE | Returns a string of the specified number of space characters | 
| STRCMP | Compares two strings | 
| SUBSTR | Extracts a substring from a string (starting at any position) | 
| SUBSTRING | Extracts a substring from a string (starting at any position) | 
| SUBSTRING_INDEX | Returns a substring of a string before a specified number of delimiter occurs | 
| TRIM | Removes leading and trailing spaces from a string | 
| UCASE | Converts a string to upper-case | 
| UPPER | Converts a string to upper-case | 
MySQL Numeric Functions
| Function | Description | 
|---|---|
| ABS | Returns the absolute value of a number | 
| ACOS | Returns the arc cosine of a number | 
| ASIN | Returns the arc sine of a number | 
| ATAN | Returns the arc tangent of one or two numbers | 
| ATAN2 | Returns the arc tangent of two numbers | 
| AVG | Returns the average value of an expression | 
| CEIL | Returns the smallest integer value that is >= to a number | 
| CEILING | Returns the smallest integer value that is >= to a number | 
| COS | Returns the cosine of a number | 
| COT | Returns the cotangent of a number | 
| COUNT | Returns the number of records returned by a select query | 
| DEGREES | Converts a value in radians to degrees | 
| DIV | Used for integer division | 
| EXP | Returns e raised to the power of a specified number | 
| FLOOR | Returns the largest integer value that is <= to a number | 
| GREATEST | Returns the greatest value of the list of arguments | 
| LEAST | Returns the smallest value of the list of arguments | 
| LN | Returns the natural logarithm of a number | 
| LOG | Returns the natural logarithm of a number, or the logarithm of a number to a specified base | 
| LOG10 | Returns the natural logarithm of a number to base 10 | 
| LOG2 | Returns the natural logarithm of a number to base 2 | 
| MAX | Returns the maximum value in a set of values | 
| MIN | Returns the minimum value in a set of values | 
| MOD | Returns the remainder of a number divided by another number | 
| PI | Returns the value of PI | 
| POW | Returns the value of a number raised to the power of another number | 
| POWER | Returns the value of a number raised to the power of another number | 
| RADIANS | Converts a degree value into radians | 
| RAND | Returns a random number | 
| ROUND | Rounds a number to a specified number of decimal places | 
| SIGN | Returns the sign of a number | 
| SIN | Returns the sine of a number | 
| SQRT | Returns the square root of a number | 
| SUM | Calculates the sum of a set of values | 
| TAN | Returns the tangent of a number | 
| TRUNCATE | Truncates a number to the specified number of decimal places | 
MySQL Date Functions
| Function | Description | 
|---|---|
| ADDDATE | Adds a time/date interval to a date and then returns the date | 
| ADDTIME | Adds a time interval to a time/datetime and then returns the time/datetime | 
| CURDATE | Returns the current date | 
| CURRENT_DATE | Returns the current date | 
| CURRENT_TIME | Returns the current time | 
| CURRENT_TIMESTAMP | Returns the current date and time | 
| CURTIME | Returns the current time | 
| DATE | Extracts the date part from a datetime expression | 
| DATEDIFF | Returns the number of days between two date values | 
| DATE_ADD | Adds a time/date interval to a date and then returns the date | 
| DATE_FORMAT | Formats a date | 
| DATE_SUB | Subtracts a time/date interval from a date and then returns the date | 
| DAY | Returns the day of the month for a given date | 
| DAYNAME | Returns the weekday name for a given date | 
| DAYOFMONTH | Returns the day of the month for a given date | 
| DAYOFWEEK | Returns the weekday index for a given date | 
| DAYOFYEAR | Returns the day of the year for a given date | 
| EXTRACT | Extracts a part from a given date | 
| FROM_DAYS | Returns a date from a numeric datevalue | 
| HOUR | Returns the hour part for a given date | 
| LAST_DAY | Extracts the last day of the month for a given date | 
| LOCALTIME | Returns the current date and time | 
| LOCALTIMESTAMP | Returns the current date and time | 
| MAKEDATE | Creates and returns a date based on a year and a number of days value | 
| MAKETIME | Creates and returns a time based on an hour, minute, and second value | 
| MICROSECOND | Returns the microsecond part of a time/datetime | 
| MINUTE | Returns the minute part of a time/datetime | 
| MONTH | Returns the month part for a given date | 
| MONTHNAME | Returns the name of the month for a given date | 
| NOW | Returns the current date and time | 
| PERIOD_ADD | Adds a specified number of months to a period | 
| PERIOD_DIFF | Returns the difference between two periods | 
| QUARTER | Returns the quarter of the year for a given date value | 
| SECOND | Returns the seconds part of a time/datetime | 
| SEC_TO_TIME | Returns a time value based on the specified seconds | 
| STR_TO_DATE | Returns a date based on a string and a format | 
| SUBDATE | Subtracts a time/date interval from a date and then returns the date | 
| SUBTIME | Subtracts a time interval from a datetime and then returns the time/datetime | 
| SYSDATE | Returns the current date and time | 
| TIME | Extracts the time part from a given time/datetime | 
| TIME_FORMAT | Formats a time by a specified format | 
| TIME_TO_SEC | Converts a time value into seconds | 
| TIMEDIFF | Returns the difference between two time/datetime expressions | 
| TIMESTAMP | Returns a datetime value based on a date or datetime value | 
| TO_DAYS | Returns the number of days between a date and date “0000-00-00” | 
| WEEK | Returns the week number for a given date | 
| WEEKDAY | Returns the weekday number for a given date | 
| WEEKOFYEAR | Returns the week number for a given date | 
| YEAR | Returns the year part for a given date | 
| YEARWEEK | Returns the year and week number for a given date | 
MySQL Advanced Functions
| Function | Description | 
|---|---|
| BIN | Returns a binary representation of a number | 
| BINARY | Converts a value to a binary string | 
| CASE | Goes through conditions and return a value when the first condition is met | 
| CAST | Converts a value (of any type) into a specified datatype | 
| COALESCE | Returns the first non-null value in a list | 
| CONNECTION_ID | Returns the unique connection ID for the current connection | 
| CONV | Converts a number from one numeric base system to another | 
| CONVERT | Converts a value into the specified datatype or character set | 
| CURRENT_USER | Returns the user name and host name for the MySQL account that the server used to authenticate the current client | 
| DATABASE | Returns the name of the current database | 
| IF | Returns a value if a condition is TRUE, or another value if a condition is FALSE | 
| IFNULL | Return a specified value if the expression is NULL, otherwise return the expression | 
| ISNULL | Returns 1 or 0 depending on whether an expression is NULL | 
| LAST_INSERT_ID | Returns the AUTO_INCREMENT id of the last row that has been inserted or updated in a table | 
| NULLIF | Compares two expressions and returns NULL if they are equal. Otherwise, the first expression is returned | 
| SESSION_USER | Returns the current MySQL user name and host name | 
| SYSTEM_USER | Returns the current MySQL user name and host name | 
| USER | Returns the current MySQL user name and host name | 
| VERSION | Returns the current version of the MySQL database | 
KAYNAK: https://www.w3schools.com/sql/sql_ref_mysql.asp
Ref: https://github.com/nuriakman/PHP-Egitimi/blob/master/konular/komutlar.mysql.all.md