auto-increment

问题 Another question today :) This time I'd like to know if/how it's possible to make a second column auto-increment for each primary key: CREATE TABLE test ( `id` INTEGER UNSIGNED NOT NULL, `subId` INTEGER UNSIGNED NOT NULL AUTO_INCREMENT, `text` VARCHAR(45) NOT NULL, PRIMARY KEY (`id`, `subId`) ) ENGINE = InnoDB; This creation, unfortunately, doesn't work, only if I specify ID as primary key and subId as index key (but I need them both together and ID can repeat...) Example data (what I need):

问题 I have an id i.e primary key and auto increment. Is there any query to update my existing id and make my id start from 1 and next id 2 and so on.. For example id name 3 ABC 5 XYZ 9 PQR NOTE: id is already primary and auto increment and I don't want truncate my id. if possible i want to get id name 1 ABC 2 XYZ 3 PQR ALTER TABLE table AUTO_INCREMENT = 1; is not my solution. Thanks 回答1: Is there any query to update my existing id and make my id start from 1 and next id 2 and so on What you can

问题 I have a model Token, which has a field token_number that I need to auto increment (starting from 1001), if and only if the user does not provide it. The problem is that, since the user has the option to provide this field, I can't exactly query the database and ask for the largest token_number. I found one answer on this forum, but I'm quite certain there has to be a better way to do it than to execute an SQL statement? Auto increment a non-primary key field in Ruby on Rails 回答1: Interesting

问题 I thought this would be simple, but I can't seem to use AUTO_INCREMENT in my db2 database. I did some searching and people seem to be using "Generated by Default", but this doesn't work for me. If it helps, here's the table I want to create with the sid being auto incremented. create table student( sid integer NOT NULL <auto increment?> sname varchar(30), PRIMARY KEY (sid) ); Any pointers are appreciated. 回答1: You're looking for is called an IDENTITY column: create table student ( sid integer

问题 I'm using php and mysql. I have a table with the id column set to auto increment as the primary key. I'm trying to add another column called sort_order. The sort_order column should auto increment when the row is inserted. Then a user will be able to change the sort_order value. But mysql does not allow auto increment for more than one column? What is the best way to auto increment the sort_order value? By popular Request, some more explanation. In administration area, the user will have a

问题 I have a table set up that currently has no primary key. All I need to do is add a primary key, no null, auto_increment . I'm working with a Microsoft SQL Server database. I understand that it can't be done in a single command but every command I try keeps returning syntax errors. edit --------------- I have created the primary key and even set it as not null. However, I can't set up the auto_increment . I've tried: ALTER TABLE tableName MODIFY id NVARCHAR(20) auto_increment ALTER TABLE

问题 Cust_ID is set to auto-increment. Initially, the insertion was not successful from my website to the database and I looked online and a suggestion was to set the PK to auto-increment. I did that and the successful data insertion message came through, however, in the database, no data was shown to be entered from the website. I attached pictures that show two attempts of insertion. The Cust_ID came back as 1 and 0 for the password and 547 for another Cust_ID. <?php require_once 'Login_Project

问题 I am trying to clone a form and change the form name from (for example) #form and when cloned to #form1 and do the same on the inputs and I am really stuck on how to do this! Any help would be GREATLY appreciated as I have spent ALL DAY trying to figure it out. Here is my code: HTML: <div class="avail"> <form action="submit.php" id="form1" method="post"> <input type="text" name="input1" /> <input type="text" name="anotherinput1" /> <input type="text" name="onemoreinput1" /> <input type=

问题 I'm having some problems writing a stored procedure to get next value of Auto Incremented column. I want to be able to pass a table name and have the value returned to a specified variable. The procedure is as follows: CREATE PROCEDURE Find_last_AI( IN table_name VARCHAR(255), OUT last_AI INT) BEGIN SELECT AUTO_INCREMENT INTO last_AI FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_SCHEMA = 'MySchema' AND TABLE_NAME = table_name LIMIT 1; END; The problem is, after I call the function like this:

问题 This script works to rename files while copying them if they are duplicates. I need to rename the current destination file first then copy the source file as is. Any ideas? function Copy-FilesWithVersioning{ Param( [string]$source, [string]$destination ) Get-ChildItem -Path $source -File ForEach-Object { $destinationFile = Join-Path $destination $file.Name if ($f = Get-Item $destinationFile -EA 0) { # loop for number goes here $i = 1 $newname = $f.Name -replace $f.BaseName, "$($f.BaseName)_$I