auto-increment

问题 CREATE TABLE IF NOT EXISTS `qdz76_piteachers` ( `id` int(11) NOT NULL AUTO_INCREMENT, `teacher_name` varchar(250) NOT NULL, `teacher_alias` varchar(250) NOT NULL, `teacher_role` varchar(50) NOT NULL, `image_folderlrg` int(11) NOT NULL, `teacher_image_lrg` varchar(250) NOT NULL, `teacher_email` varchar(100) NOT NULL, `teacher_website` varchar(250) NOT NULL, `teacher_description` text NOT NULL, `published` tinyint(3) NOT NULL, `ordering` int(11) NOT NULL, `teacher_view` tinyint(3) NOT NULL,

问题 I have a question concerning the deletion of a row in a sql database. My methods use the id from a onItemClick listener to identify the clicked object but as soon as one item is deleted, these id's don't work anymore because they don't match the id row in the database. Here's an example to clarify what I mean: ListView in Android Item 1 (id 0) Item 2 (id 1) Item 3 (id 2) Database (id gets corrected with +1 to match up) Item 1 (id 1) Item 2 (id 2) Item 3 (id 3) After deletion ListView Item 1

问题 I am using keyholder to get the id that is automatically incremented while inserting. It works fine on the actual table. I have a synonym table in another database which actually points to the original table and I have to do the insert into the synonym table. The method used is returning 0 for keyholder.getkey() when I try to do the insert in the synonym table. Please help me.. References: https://stackoverflow.com/questions/241003/how-to-get-a-value-from-the-last-inserted-row http://docs

问题 I'm getting this error in puTTY. Not sure why, looks right to me ... psql:pierre.sql:10: ERROR: syntax error at or near "AUTO_INCREMENT" LINE 2: c_id INTEGER NOT NULL AUTO_INCREMENT PRIMARY KEY, ^ psql:pierre.sql:18: ERROR: syntax error at or near "AUTO_INCREMENT" LINE 2: r_id INTEGER NOT NULL AUTO_INCREMENT PRIMARY KEY, --DROP TABLE customer, reservation; CREATE TABLE customer( c_id INTEGER NOT NULL AUTO_INCREMENT PRIMARY KEY, c_ref VARCHAR(30) NOT NULL, f_name VARCHAR(30) NOT NULL, l_name

问题 I would like to create a unique hash of an AUTO-INCREMENT field while inserting that row. Something like: INSERT INTO `table` (`hash`,`salt`) VALUES (MD5(CONCAT(`id`,`salt`)),'1234789687'); Is it possible to use the AUTO-INCREMENTED id of the row WHILE I'm inserting? Or do I have to wait until it's inserted to grab it via PHP or something? 回答1: The short answer is no- it is not possible. If your db has low transaction volume, then concurrency may not be an issue to use something similar to

问题 I have a table named GROUPS which has a column GROUP_ID whose values are GRP001, GRP002, GRP003 and so on. Now every time I insert a new row I have to insert it with a (current) GROUP_ID= (highest)GROUP_ID+ 1 , for example if highest GROUP_ID= GRP003 I have to generate a new GROUP_ID GRP004 when I insert a new row. How can I do this using java? I am currently using Hibernate along with Struts 2 in my program Is there any way to deal with this using hibernate? Or will I have to write

问题 I have a simple INSERT INTO t1 (fields...) (SELECT fields... FROM t2); it inserts around 8.000 rows and the auto increment value of the table is set to ~16.000, but it's not exactly 2x as much. I don't include the auto incremented id in the query, and the tables are truncated. Can it be a bug? I have version 5.5.24. Why is that, and how can I avoid this? CREATE TABLE `order` ( `id` int(10) unsigned NOT NULL AUTO_INCREMENT, `` int(4) NOT NULL COMMENT '', `` int(6) NOT NULL COMMENT '', ``

问题 I have query in MS ACCESS 2016 that I need to add autonumber to. Basically, the query output results in one column of data and I want to add a new column to this output with numbers starting from 1 to whatever the row count of the query output will be. I dont want to create a new table from my query output though. Is there a way to do this in a query? I managed to add a new ID column that just has a scalar value, however what I need is auto increment here. Any thoughts? SELECT qry.ColA, 1 AS

问题 This may have a really easy answer. I have done much database stuff for a while. I am trying to get the auto_increment value from one table inserted into the value on another table. is there an easy way of doing this. For eg i have done: CREATE TABLE table_a ( id int NOT NULL AUTO_INCREMENT, a_value varchar(4), PRIMARY KEY (id) ); CREATE TABLE table_b ( id int NOT NULL, b_value varchar(15), FOREIGN KEY (id) REFERENCES table_a (id) ); Now i want to insert values into the table but I would like

问题 I am trying to: Loop through a bunch of files makes some changes Copy the old file to a sub directory. Here's the kicker I don't want to overwrite the file in the new directory if it already exists. (e.g. if "Filename.mxd" already exists, then copy and rename to "Filename_1.mxd". If "Filename_1.mxd" exists, then copy the file as "Filename_2.mxd" and so on...) save the file (but do a save, not a save as so that it overwrites the existing file) it goes something like this: for filename in glob