constraints

问题 In connection with this answer I stumbled upon a phenomenon I cannot explain. Version: PostgreSQL 9.1.2 on x86_64-unknown-linux-gnu, compiled by gcc-4.4.real (Debian 4.4.5-8) 4.4.5, 64-bit Consider the following demo. Testbed: CREATE TEMP TABLE t ( id integer ,txt text ,CONSTRAINT t_pkey PRIMARY KEY (id) DEFERRABLE INITIALLY IMMEDIATE ); INSERT INTO t VALUES (1, 'one') ,(2, 'two'); 1) UPDATE statement modifying multiple rows: UPDATE t SET id = t_old.id FROM t t_old WHERE (t.id, t_old.id) IN (

问题 Can some one please tell me why this is not animating? I feel that the code is all perfect but the animate function is not working. The button is jumping instantly from side to side but like i said it isn't animating... func moveResetButton( constraint : NSLayoutConstraint, isOffScreen : Bool) { if isOffScreen { //animate the button onto the screen UIView.animate(withDuration: 3.0, delay: 0.0, options: .curveLinear, animations: { constraint.constant += 120 }, completion: nil) } else { /

问题 how to give constraints for the buttons in the bottom as shown in image. 回答1: select all 5 UIButtons and give equal widths constraints. give following constraints forr all buttons: 1.Height constraint. 2.Leading Constraint. 2.Bottom Constrain. 4.Equal Width Constraint 5.Trailing Constraint(if necessary) check here :Arrange 3 UIButtons(of equal width) side-by-side 来源： https://stackoverflow.com/questions/36515549/how-to-give-constraints-for-uibuttons

问题 I am using auto layout in storyboard with all resolution support,but I am stuck on one thing that.I want flexible horizontal spacing between my labels using constraints.Please see screenshot for more details. This is a 4.7inch screen.This screen is correct as I designed for particularly this screen 4 inch screen 5.5 inch IPad screen Please help to manage my labels spacing equally in all supported resolutions with auto layout and constraints. Edit This is my view hierarchy and it is also a

问题 I try to remove constraints. I want to different constraints on portrait and landscape. If I change the orientation to Portrait I call the function setupConstrainsInPortrait and conversely. I have two functions. This function setup Portrait mode. func setupConstrainsInPortrait() { view.addSubview(myView) myView.centerXAnchor.constraint(equalTo: view.centerXAnchor).isActive = true myView.topAnchor.constraint(equalTo: view.topAnchor, constant: 50).isActive = true myView.heightAnchor.constraint

问题 Is it possible to create an unique constraint on a table column, which ignores any non-alphanumeric characters? Especially spaces, dashes and slashes? The constraint should, for example, trigger, if the table already contains a string "test" and the user create a new dataset with the text "te-st" or "t e s t" or even "t - es/t". The table only allows lowercase letters. 来源： https://stackoverflow.com/questions/57710047/unique-constraint-that-only-considers-alphanumeric-characters-on-sql-server

问题 Is it possible to create an unique constraint on a table column, which ignores any non-alphanumeric characters? Especially spaces, dashes and slashes? The constraint should, for example, trigger, if the table already contains a string "test" and the user create a new dataset with the text "te-st" or "t e s t" or even "t - es/t". The table only allows lowercase letters. 来源： https://stackoverflow.com/questions/57710047/unique-constraint-that-only-considers-alphanumeric-characters-on-sql-server

问题 I'm using Oracle 10g Express and trying to delete records from tables with bi-directional constraints. I'm trying to un-thread hundreds of tables and dependencies generated via Hibernate (which can't be changed at this point), but here is an extremely simplified example: create table TableA (id number(19,0) not null, ..., rTableA_id number(19,0), primary key (id)); create table TableB (id number(19,0) not null, ..., rTableB_id number(19,0), primary key (id)); alter table TableA add constraint

问题 I followed a laracast series and stuck at some point. I got the following error message by trying to submit a blog post: QueryException in Connection.php line 713: SQLSTATE[23000]: Integrity constraint violation: 1452 Cannot add or update a child row: a foreign key constraint fails ( codeshare . articles , CONSTRAINT articles_user_id_foreign FOREIGN KEY ( user_id ) REFERENCES users ( id ) ON DELETE CASCADE) (SQL: insert into articles ( title , body , published_at , updated_at , created_at )

问题 What is the best way to express range constraint in JPA? I would like to express something like 'this column can only take values between 1..5'. Probably I could use @PrePersist and @PreUpdate for that. Is there a better way? 回答1: The Bean validation (JSR 303) is a standard , Hibernate Validator is just an implementation (the RI more precisely) so this doesn't really tie you with Hibernate. And although Bean Validation 1.0 is part of Java EE 6, it can be used "outside" a Java EE 6 container.