check-constraints

问题 This question already has answers here : CHECK constraint in MySQL is not working (8 answers) Closed 11 months ago . check constraint won't work CREATE TABLE IF NOT EXISTS supervisor ( sup_id INT(3) NOT NULL, sup_name VARCHAR(30) NOT NULL, gen VARCHAR(1) NOT NULL CHECK (gen='M' or gen='F'), dep_id INT(4), PRIMARY KEY (sup_id), INDEX (dep_id), FOREIGN KEY (dep_id) REFERENCES department(dep_id) ON UPDATE CASCADE ON DELETE RESTRICT ); i also tried: CONSTRAINT chk_supervisor_gen CHECK ('M' or 'F'

问题 This question already has answers here : CHECK constraint in MySQL is not working (8 answers) Closed 11 months ago . check constraint won't work CREATE TABLE IF NOT EXISTS supervisor ( sup_id INT(3) NOT NULL, sup_name VARCHAR(30) NOT NULL, gen VARCHAR(1) NOT NULL CHECK (gen='M' or gen='F'), dep_id INT(4), PRIMARY KEY (sup_id), INDEX (dep_id), FOREIGN KEY (dep_id) REFERENCES department(dep_id) ON UPDATE CASCADE ON DELETE RESTRICT ); i also tried: CONSTRAINT chk_supervisor_gen CHECK ('M' or 'F'

问题 This question already has answers here : CHECK constraint in MySQL is not working (8 answers) Closed 10 months ago . Here I want to create 2 CHECK constraint before the record insert to the database. ALTER TABLE SubjectEnrollment ADD CONSTRAINT register CHECK (register <= classSize AND register >=0), ADD CONSTRAINT available CHECK (available <= classSize AND available >= 0); register attribute should not more than classSize attribute and less than 0. available attribute should not more than

问题 I want to add a field-level validation on a table. There is a field named "account_number" and this field should always pass a "luhn" check. I've found a function called "luhn_verify" that seems to work properly (google for it if you are interested). It returns a boolean. My question is: Are there any major performance advantages in PostgreSQL for using a trigger for this validation vs. a check constraint. Additional information: PostgreSQL 9.1 Table does not currently have an insert trigger,

问题 What SQL databases, if any, support subqueries in CHECK constraints? At present and as far as I know, Oracle, MySQL, and PostgreSQL do not. EDIT (Clarification based on initial answers.) I'm looking for something like this: CREATE TABLE personnel ( ..., department VARCHAR(64) NOT NULL, salary NUMERIC NOT NULL, CHECK (salary >= (SELECT MIN(p.salary) FROM payranges p WHERE p.dept = department) AND salary <= (SELECT MAX(p.salary) FROM payranges p WHERE p.dept = department) ) UPDATE MS Access and

问题 It seems that some scripts generated by Enterprise Manager* (or not, it doesn't matter) created check constraints WITH NOCHECK . Now when anyone modifies the table, SQL Server is stumbling across failed check constraints, and throwing errors. Can i make SQL go through all its check constraints, and check them? Running: sp_msforeachtable 'ALTER TABLE ? CHECK CONSTRAINT all' only enables previously disabled check constraints, it doesn't actually check them. Footnotes * SQL Server 2000 回答1: DBCC

问题 It seems that some scripts generated by Enterprise Manager* (or not, it doesn't matter) created check constraints WITH NOCHECK . Now when anyone modifies the table, SQL Server is stumbling across failed check constraints, and throwing errors. Can i make SQL go through all its check constraints, and check them? Running: sp_msforeachtable 'ALTER TABLE ? CHECK CONSTRAINT all' only enables previously disabled check constraints, it doesn't actually check them. Footnotes * SQL Server 2000 回答1: DBCC

问题 I have a database that records breeding information for cows in Microsoft SQL Server 2012 Express. Obviously, a cow cannot be bred until after she is born, and she may be bred multiple times during her life; and I need to enforce these constraints in my database. I currently have arranged a schema according to the following diagram: DataID is the primary key for all animals. I have attempted to implement Table-Per-Type inheritance, hence the 1-to-1 relationship between [Animals].[Master] and

问题 I have a database that records breeding information for cows in Microsoft SQL Server 2012 Express. Obviously, a cow cannot be bred until after she is born, and she may be bred multiple times during her life; and I need to enforce these constraints in my database. I currently have arranged a schema according to the following diagram: DataID is the primary key for all animals. I have attempted to implement Table-Per-Type inheritance, hence the 1-to-1 relationship between [Animals].[Master] and

问题 This question already has answers here : CHECK constraint in MySQL is not working (8 answers) Closed 10 months ago . Can anyone help me correctly write the correct syntax for a CHECK CONSTRAINT IN MYSQL. My table is as follows and am having an error on declaring a CHECK constraint for STATUS. CREATE TABLE EventRequest ( EventNo CHAR(8) NOT NULL, DateHeld DATE NOT NULL, DateReq DATE NOT NULL, FacNo CHAR(8)NOT NULL, CustNo CHAR(8) NOT NULL, DateAuth DATE, Status CHAR(8)NOT NULL, EstCost DECIMAL