MySQL – functions, administrative commands, datatypes

 0    161 flashcards    sir
download mp3 print play test yourself
 
Question język polski Answer język polski
Returns the ASCII value for the specific character
start learning
ASCII(text)
Returns the length of a string (in characters)
start learning
CHARACTER_LENGTH(text)
=CHAR_LENGTH(text)
Concatenates two or more expressions together
start learning
CONCAT(arg1, arg2, ...)
Concatenates two or more expressions together with a separator
start learning
CONCAT_WS(sep, arg1, arg2, ...)
Returns the index position of a value in a list of values
start learning
FIELD(arg1, arg2, ...)
Returns the position of a string within A LIST OF strings
start learning
FIND_IN_SET(searched_string, s1, s2, s3, ...)
Formats a number to a format like "#,###,###.##", rounded to a specified number of decimal places
FORMAT(12678.90, 2)
start learning
FORMAT(number, decimals)
"12,678,90"
Inserts a string within a string at the specified position and for a certain number of characters
start learning
INSERT(text, position, n, s)
n − number of characters to replace
Returns the position of the first occurrence of a string in another string
start learning
INSTR(text, s)
Converts a string to lower-case
start learning
LCASE(text)
=LOWER(text)
Extracts a number of characters from a string (starting from left)
start learning
LEFT(text, n)
Returns the length of a string (in bytes)
start learning
LENGTH(text)
Returns the position of the first occurrence of a substring in a string
start learning
LOCATE(s, text, start)
=POSITION(...)
Left-pads a string with another string, to a certain length
start learning
LPAD(text, width, s)
Corresponds Python 3 rjust()
Removes leading spaces from a string
start learning
LTRIM(text)
Repeats a string as many times as specified
start learning
REPEAT(text, n)
Replaces all occurrences of a substring within a string, with a new substring
start learning
REPLACE(text, s1, s2)
Similar to Python's 3.
Reverses a string and returns the result
start learning
REVERSE(text)
Extracts a number of characters from a string (starting from right)
start learning
RIGHT(text, n)
Right-pads a string with another string, to a certain length
start learning
RPAD(text, width, s)
Removes trailing spaces from a string
start learning
RTRIM(text)
Returns a string of the specified number of spaces.
start learning
SPACE(number)
Compares two strings
start learning
STRCMP(s1, s2)
returns -1 or 0 or 1
Extracts a substring from a string (starting at any position)
start learning
SUBSTRING(text, start, len)
=SUBSTR(...)=MID(...)
Returns a substring of a string before a specified number of DELIMITER occurs
start learning
SUBSTRING_INDEX(text, delimiter, quantity)
Removes leading and trailing spaces from a string
start learning
TRIM(text)
Converts a string to upper-case
start learning
UCASE(text)
=UPPER(text)
Adds a time/date interval to a date and then returns the date
start learning
ADDDATE(date/datetime, interval)
adddate(current_date(), INTERVAL 3 minute)
Adds a time interval to a time/datetime and then returns the time/datetime
start learning
ADDTIME(time/datetime, interval)
Returns the current date
start learning
CURRENT_DATE()
=CURDATE()
Returns the current time
start learning
CURRENT_TIME()
=CURTIME()
Extracts the date part from a datetime expression
start learning
DATE(datetime)
Returns the number of days between two date values
start learning
DATEDIFF(date1, date2)
Adds a time/date interval to a date and then returns the date
start learning
DATE_ADD(date, interval)
Formats a date
start learning
DATE_FORMAT(date, format_specifier)
Subtracts a time/date interval from a date and then returns the date
start learning
DATE_SUB(date, interval)
Returns the day of the month for a given date
start learning
DAY(date[time])
Returns the weekday NAME for a given date
start learning
DAYNAME(date[time])
Returns the day of the month for a given date
start learning
DAYOFMONTH(date[time])
Returns the weekday number for a given date
start learning
DAYOFWEEK(date[time])
Returns the day of the year for a given date
start learning
DAYOFYEAR(date[time])
Extracts a part from a given date
start learning
EXTRACT(time_unit FROM date/time)
Returns a date from a numeric datevalue
start learning
FROM_DAYS(day_quantity)
Returns the hour part for a given date
start learning
HOUR([date]time)
Extracts the last day of the month for a given date
start learning
LAST_DAY([date]time)
Returns the current date and time
start learning
NOW()
LOCALTIMESTAMP(), localtime(), sysdate(), CURRENT_TIMESTAMP()
Creates and returns a date based on a year and a number of days value
start learning
MAKEDATE(year, minute, second)
Creates and returns a time based on an hour, minute, and second value
start learning
MAKETIME(hour, minute, second)
Returns the microsecond part of a time/datetime
start learning
MICROSECOND([date]time)
Returns the minute part of a time/datetime
start learning
MINUTE([date]time)
Returns the month part for a given date
start learning
MONTH(date[time])
Returns the name of the month for a given date
start learning
MONTHNAME(date[time])
Adds a specified number of months to a period
start learning
PERIOD_ADD(period, number)
SELECT PERIOD_ADD(201703, 15);
Returns the difference between two periods
start learning
PERIOD_DIFF(period, number)
SELECT PERIOD_DIFF(1703, 1612);
Returns the quarter of the year for a given date value
start learning
QUARTER([date]time)
Returns the seconds part of a time/datetime
start learning
SECOND([date]time)
Returns a time value based on the specified seconds
start learning
SEC_TO_TIME(seconds)
Returns a date based on a string and a format
start learning
STR_TO_DATE(text, format_specifier)
Subtracts a time/date interval from a date and then returns the date
start learning
SUBDATE(date, interval)
Subtracts a time interval from a datetime and then returns the time/datetime
start learning
SUBTIME(time, interval)
Extracts the time part from a given time/datetime
start learning
TIME(datetime)
Formats a time by a specified format
start learning
TIME_FORMAT(time, format_specifier)
Converts a time value into seconds
start learning
TIME_TO_SEC(time)
Returns the difference between two time/datetime expressions
start learning
TIMEDIFF(t1, t2)
Returns a datetime value based on a date or datetime value
start learning
TIMESTAMP(date[time], [time])
Returns the number of days between a date and date "0000-00-00"
start learning
TO_DAYS(date)
Returns the week number for a given date
start learning
WEEK(date[time])
Returns the weekday number for a given date
start learning
WEEKDAY(date[time)
Returns the week number for a given date
start learning
WEEKOFYEAR(date[time)
Returns the year part for a given date
start learning
YEAR(date[time)
Returns the year and week number for a given date
start learning
YEARWEEK(date[time)
Returns the absolute value of a number
start learning
ABS(x)
Returns the arc cosine of a number
start learning
ACOS(x)
Returns the arc sine of a number
start learning
ASIN(x)
Returns the arc tangent of one or two numbers
start learning
ATAN(x)
Returns the arc tangent of two numbers
start learning
ATAN2(x, y)
Returns the average value of an expression
start learning
AVG(column)
Returns the smallest integer value that is >= to a number
start learning
CEILING(x)
=CEIL(x)
Returns the cosine of a number
start learning
COS(x)
Returns the cotangent of a number
start learning
COT(x)
Returns the number of records returned by a select query
start learning
COUNT(column)
Converts a value in radians to degrees
start learning
DEGREES(x)
Used for integer division
start learning
DIV
5 div 2 = 2
Returns e raised to the power of a specified number
start learning
EXP(x)
Returns the largest integer value that is <= to a number
start learning
FLOOR(x)
Returns the greatest value of the list of arguments
start learning
GREATEST(arg1, arg2, ...)
Returns the smallest value of the list of arguments
start learning
LEAST(arg1, arg2, ...)
Returns the natural logarithm of a number
start learning
LN(x)
Returns the natural logarithm of a number, or the logarithm of a number to a specified base
start learning
LOG(base, x)
wheras: LOG(x)=LN(x)
Returns the logarithm of a number to base 10
start learning
LOG10(x)
Returns the logarithm of a number to base 2
start learning
LOG2(x)
Returns the maximum value in a set of values
start learning
MAX(column)
Returns the minimum value in a set of values
start learning
MIN(column)
Returns the remainder of a number divided by another number
start learning
x MOD y
=MOD(x,y)=x%y
Returns the value of PI
start learning
PI()
Returns the value of a number raised to the power of another number
start learning
POWER(x, y)
POW(x,y)
Converts a degree value into radians
start learning
RADIANS(x)
Returns a random number x, where x∈⟨0;1)
start learning
RAND()
the same as Python 3 random. random()
Rounds a number to a specified number of decimal places
start learning
ROUND(x,y)
Returns the sign of a number
start learning
SIGN(x)
Returns the sine of a number
start learning
SIN(x)
Returns the square root of a number
start learning
SQRT(x)
Calculates the sum of a set of values
start learning
SUM(column)
Returns the tangent of a number
start learning
TAN(x)
Truncates a number to the specified number of decimal places
start learning
TRUNCATE(x)
Returns a binary representation of a number
start learning
BIN(x)
Attention it AIN'T the same as BINARY()
Converts a value to a binary string
start learning
BINARY value
Converts a value (of any type) into a specified datatype
start learning
CAST(value AS datetype)
Returns the first non-null value in a list
start learning
COALESCE(*args)
Returns the unique connection ID for the current connection
start learning
CONNECTION_ID()
Converts a number from one numeric base system to another
start learning
CONV(n, base, new_base)
Converts a value into the specified datatype or character set
start learning
CONVERT(value, datatype)
Returns the name of the current database
start learning
DATABASE()
Returns a value if a condition is TRUE, or another value if a condition is FALSE
start learning
IF(condition, value1, value2)
Return a specified value if the expression is NULL, otherwise return the expression
start learning
IFNULL(value)
Returns 1 or 0 depending on whether an expression is NULL
start learning
ISNULL(value)
Returns the AUTO_INCREMENT id of the last row that has been inserted or updated in a table
start learning
LAST_INSERT_ID()
Compares two expressions and returns NULL if they are equal. Otherwise, the first expression is returned
start learning
NULLIF(value, value2)
Returns the current MySQL user name and host name
start learning
USER()
=CURRENT_USER()=SYSTEM_USER=SESSION_USER
Returns the current version of the MySQL database
start learning
VERSION()
This will be used to select a database in the MySQL workarea.
start learning
USE Databasename;
Lists out the databases that are accessible by the MySQL DBMS.
start learning
SHOW DATABASES;
Shows the tables in the database once a database has been selected with the use command.
start learning
SHOW TABLES;
Shows the attributes, types of attributes, key information, whether NULL is permitted, defaults, and other information for a table.
start learning
SHOW COLUMNS FROM tablename;
Presents the details of all indexes on the table, including the PRIMARY KEY.
start learning
SHOW INDEX FROM tablename
Reports details of the MySQL DBMS performance and statistics.
start learning
SHOW TABLE STATUS LIKE tablename;
A FIXED length string (can contain letters, numbers, and special characters). The size parameter specifies the column length in characters - can be from 0 to 255. Default is 1
start learning
CHAR(size)
A VARIABLE length string (can contain letters, numbers, and special characters). The size parameter specifies the maximum column length in characters - can be from 0 to 65535
start learning
VARCHAR(size)
Equal to CHAR(), but stores binary byte strings. The size parameter specifies the column length in bytes. Default is 1
start learning
BINARY(size)
Equal to VARCHAR(), but stores binary byte strings. The size parameter specifies the maximum column length in bytes.
start learning
VARBINARY(size)
For BLOBs (Binary Large OBjects). Max length: 255 bytes
start learning
TINYBLOB
Holds a string with a maximum length of 255 characters
start learning
TINYTEXT
Holds a string with a maximum length of 65,535 bytes
start learning
TEXT(size)
For BLOBs (Binary Large OBjects). Holds up to 65,535 bytes of data
start learning
BLOB(size)
Holds a string with a maximum length of 16,777,215 characters
start learning
MEDIUMTEXT
For BLOBs (Binary Large OBjects). Holds up to 16,777,215 bytes of data
start learning
MEDIUMBLOB
Holds a string with a maximum length of 4,294,967,295 characters
start learning
LONGTEXT
For BLOBs (Binary Large OBjects). Holds up to 4,294,967,295 bytes of data
start learning
LONGBLOB
A string object that can have only one value, chosen from a list of possible values.
You can list up to 65535 values in an ENUM list. If a value is inserted that is not in the list, a blank value will be inserted. The values are sorted in the order you enter them
start learning
ENUM(val1, val2, val3, ...)
A string object that can have 0 or more values, chosen from a list of possible values. You can list up to 64 values in a SET list
start learning
SET(val1, val2, val3, ...)
A bit-value type. The number of bits per value is specified in size. The size parameter can hold a value from 1 to 64. The default value for size is 1.
start learning
BIT(size)
A very small integer. Signed range is from -128 to 127. Unsigned range is from 0 to 255. The size parameter specifies the maximum display width (which is 255)
start learning
TINYINT(size)
Zero is considered as false, nonzero values are considered as true.
start learning
BOOL
Equal to BOOL
start learning
BOOLEAN
A small integer. Signed range is from -32768 to 32767. Unsigned range is from 0 to 65535. The size parameter specifies the maximum display width (which is 255)
start learning
SMALLINT(size)
A medium integer. Signed range is from -8388608 to 8388607. Unsigned range is from 0 to 16777215. The size parameter specifies the maximum display width (which is 255)
start learning
MEDIUMINT(size)
A medium integer. Signed range is from -2147483648 to 2147483647. Unsigned range is from 0 to 4294967295. The size parameter specifies the maximum display width (which is 255)
start learning
INT(size)
Equal to INT(size)
start learning
INTEGER(size)
A large integer. Signed range is from -9223372036854775808 to 9223372036854775807. Unsigned range is from 0 to 18446744073709551615. The size parameter specifies the maximum display width (which is 255)
start learning
BIGINT(size)
A floating point number. The total number of digits is specified in size. The number of digits after the decimal point is specified in the d parameter. This syntax is deprecated in MySQL 8.0.17, and it will be removed in future MySQL versions
start learning
FLOAT(size, d)
A floating point number. MySQL uses the p value to determine whether to use FLOAT or DOUBLE for the resulting data type. If p is from 0 to 24, the data type becomes FLOAT(). If p is from 25 to 53, the data type becomes DOUBLE()
start learning
FLOAT(p)
A normal-size floating point number. The total number of digits is specified in size. The number of digits after the decimal point is specified in the d parameter
start learning
DOUBLE(size, d)
An exact fixed-point number. The total number of digits is specified in size.
The number of digits after the decimal point is specified in the d parameter. The maximum number for size is 65. The maximum number for d is 30. The default value for size is 10. The default value for d is 0.
start learning
DECIMAL(size, d)
Equal to DECIMAL(size,d)
start learning
DEC(size, d)
To disable negative numbers.
start learning
UNSIGNED
To add leading zeros, which make all numbers in the column sustain the same length.
start learning
ZEROFILL
A date. Format: YYYY-MM-DD. The supported range is from '1000-01-01' to '9999-12-31'
start learning
DATE
A date and time combination. Format: YYYY-MM-DD hh: mm: ss.
The supported range is from '1000-01-01 00:00:00' to '9999-12-31 23:59:59'. Adding DEFAULT and ON UPDATE in the column definition to get automatic initialization and updating to the current date and time
start learning
DATETIME(fsp)
A timestamp. TIMESTAMP values are stored as the number of seconds since the Unix epoch ('1970-01-01 00:00:00' UTC). Format: YYYY-MM-DD hh: mm: ss.
The supported range is from '1970-01-01 00:00:01' UTC to '2038-01-09 03:14:07' UTC.
start learning
TIMESTAMP(fsp)
A time. Format: hh: mm: ss. The supported range is from '-838:59:59' to '838:59:59'
start learning
TIME(fsp)
A year in four-digit format. Values allowed in four-digit format: 1901 to 2155, and 0000.
start learning
YEAR

You must sign in to write a comment