El valor inicial para AUTO_INCREMENT para la tabla. En MySQL 5.0, sólo funciona para tablas MyISAM y MEMORY. También se soporta para InnoDB desde MySQL 5.0.3. Para inicializar el primer valor de auto incremento para motores que no soporten esta opción, inserte un registro de prueba con un valor que sea uno menor al deseado… Leer más »
“Si me quieres, te querrémás y más a cada instante mientras vivaporque si no me quieres no soy nada” «Mi esperanza es ser parte de tu vida y que tú seas parte de la mía.» Tags: friki, php
MySQL: CREATE TABLE ORDERS (Order_ID integer, Order_Date date, Customer_SID integer, Amount double, Primary Key (Order_ID), Foreign Key (Customer_SID) references CUSTOMER(SID)); Oracle: CREATE TABLE ORDERS (Order_ID integer primary key, Order_Date date, Customer_SID integer references CUSTOMER(SID), Amount double); SQL Server: CREATE TABLE ORDERS (Order_ID integer primary key, Order_Date datetime, Customer_SID integer references CUSTOMER(SID), Amount double); Below are… Leer más »
MySQL migration: MyISAM to InnoDB By Keith Winston on July 18, 2005 (8:00:00 AM) The MySQL database is unique in that it offers multiple storage engines. The SQL parser and front end interfaces are separate from the storage engines, so you can choose among nine low-level table formats the one that suits your application… Leer más »
Simply put, referential integrity means that when a record in a table refers to a corresponding record in another table, that corresponding record will exist. Look at the following:
update tablename set field = replace(field,’search_for_this’,’replace_with_this’); Tags: search, replace, mysql
Getting the recent one month or year records from MySQL tableSome time we have to collect last 7 or 15 days or X days (or month, year or week) data from MySQL table. For example let us find out who are the new members joined in our forum in last week. One shop may be… Leer más »
http://www-128.ibm.com/developerworks/systems/library/es-nweb.html?ca=drs–
Concatenar strings $str1 = “hola “;$str2 = “que tal “;$str3= “como estas?”; $str4 = $str1.$str2.$str3; Strings CharsSe pueden reemplazar los caracteres:$str1 = «0123456789″;$str1[2]=»x«; Cambiar a mayusculas y minúsculas:strtoupper();strtolower(); Capitaliza la primera letra:ucfirst(); Capitaliza todas las letras:ucwords();ASCII chr(32) = spacechr(65) = A ord(“A”) = 65; Tags: strings
unset() Syntax: void unset(mixed var [, mixed var, …])var Variable to unset. Unsets a variable. unset() destroys one or more variables and deallocates the memory associated with them. Code: <?php $a = «Some data»; unset($a); if (!isset($a)) { print «\$a is no longer available»; } ?> Output: $a is no longer available