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Este Cmap, tiene información relacionada con: SELECT, LIKE Pattern matching using SQL simple regular expression comparison Syntax <expression> LIKE '%value%' <expression> LIKE '_value_', FUNTIONS Agregation Aggregate functions compute summaries of data in a table COUNT The number of rows SUM The sum of the entries in a column AVG The average entry in a column MIN, MAX The minimum and maximum entries in a column, =, <, >, <> syntax <column-list|value|'str'> =|<|>|<> <column-list|value|'str'>, Functions Boolean <condition>AND<condition> <condition>OR<condition>, (NOT) IN See if a given value is in(or not in) a set of values Comparison (NOT) BETWEEN...AND... Check whether a value is within a range of values, (NOT) BETWEEN...AND... Check whether a value is within a range of values Syntax <expression> BETWEEN <value> AND <value>, SELECT is for To retrieve rows selected from one or more tables, SELECT Syntax SELECT [DISTINCT | ALL] <column-list> AS <column-name> FROM <table-names> <conditions>, IS (NOT) NULL Tests whether a value is or not NULL. Important Is not the same: Phone = NULL vs Phone = 'NULL', FUNTIONS String CONCAT(expr1,expr2,...) Returns a concatenated string STRCMP(expr1,expr2) Compare two strings. CHAR(num1) Returns the character for each integer passed CHAR_LENGTH(str) Returns the length of the string str, measured in characters LOWER(str) Return the argument in lowercase UPPER(str) Return the argument in uppercase REVERSE(str) Reverse the characters in a string REPLACE(str,from_str,to_str) Returns the string str with all occurrences of the string from_str replaced by the string to_str. LOCATE(substr,str,pos) Returns the position of the first occurrence of substring substr in string str, starting at position pos. SUBSTRING(str,pos) Return a substring from string str starting at position pos, SELECT [DISTINCT | ALL] <column-list> AS <column-name> FROM <table-names> <conditions> Condition WHERE Indicates the condition or conditions that rows must satisfy to be selected and can include UNION statements and subqueries. you can use any of the functions and operators that MySQL supports, except for aggregate functions, SELECT [DISTINCT | ALL] <column-list> AS <column-name> FROM <table-names> <conditions> To FUNTIONS, (column list) AS: To display the column with a different name Column Expression DISTINCT: Used to get non repeated data ALL: Default value. Show all data, WHERE Indicates the condition or conditions that rows must satisfy to be selected and can include UNION statements and subqueries. you can use any of the functions and operators that MySQL supports, except for aggregate functions Syntax SELECT <column-list> FROM <table-names> [WHERE <condition>], =, <, >, <> Operators Functions, Important to note the precedence of operators This precedence can be changed with the use of brackets () Functions ROUND(X,D) Round the argument to D decimals (default is 0) TRUNCATE(X,D) Returns the number X, truncated to D decimal places (default is 0) POW(num) Return the argument raised to the specified power SQRT(num) Return the square root of the argument, LIKE Pattern matching using SQL simple regular expression comparison Symbols %: sequence of zero or more characters; _ (underscore): any single character., (NOT) IN See if a given value is in(or not in) a set of values Syntax WHERE <value> IN|NOT IN <set>, (NOT) IN See if a given value is in(or not in) a set of values Comparison Functions, FUNTIONS Date CURDATE() Return the current date NOW() Return the current date and time CURRENT_TIME() Return the current time DAYNAME(date) Return the name of the weekday DAYOFMONTH(date) Return the day of the month (031) DAYOFYEAR(date) Return the day of the year (1366) WEEKDAY() Return the weekday index YEAR() Return the year MINUTE(time) DATEDIFF(expr1,expr2) ADDTIME(expr1,expr2) DATE_FORMAT(date,format) Formats the date value according to the format string