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The attribute column name (EXCEPTION) is a reserved SQL-99 keyword.

How do I fix this error/warning that Netbeans gives me? "The attribute column name (EXCEPTION ... but could be with other DBMS. To remove the warning, either rename your field (e.g. to exceptionText), or add a Column annotation that will map the name of the Java field to another name in the database: @Column(name

@Column length is not working.

I am using objectdb 2.8.3, I have a Entity class with a column that is declared as @Column(unique = true, nullable = false, length = 16) but when i m trying to insert a string for that column ... so its very difficult to validate the column string length. Please find the below project and objectdb file

Order in WHERE Clause affects behaviour on DATE/DATETIME columns

Quick example: public class MyClass { @Column(name = "myText") String myText; @Temporal(TemporalType.TIMESTAMP) @Column(name = "myDate") Date myDate; } Now ... obviously makes a difference. The date column seems to be converted to a String

@Column( name = "columnName") doesn't work

{ @Id @GeneratedValue @Column(name = "KEY_ID") private long id; private Long timestamp; @ManyToOne @Column(name = "KEY_DESCRIPTOR") private AfwKeyDescriptor keyDescriptor; @OneToMany(fetch = FetchType.LAZY, cascade = CascadeType.ALL) @Column( name = "DATA_ITEMS

Adding new unique columns

What is the best practice for when you need to add a new unique column to an existing database? Simply adding the column with the @Unique annotation will result in "Attempt to reuse an existing value (null)", so the only option I can surmise is to add the column, update all existing entries

drop a column from table

Hi, I want to drop one column from my database table suppose i have 3 column (id, name, address) now i want to drop address. then what will be the query or procedure.. Bimal Bimal kumar dalei Just ... But it physically present and logically it will not display. If a want to drop or delete a column

Index on a low cardinality column

up queries." "An index on the gender column likely would not help because there's no value in an index on a low cardinality column. Meaning, there's not enough variety in the values for the index to provide any value." an index on a low cardinality column is generally not recommended as mentioned


Annotation Element javax.persistence.SqlResultSetMapping ColumnResult[] columns Specifies the result set mapping to scalar values. Default value: {} Since: JPA 1.0


a column for joining an entity association or element collection. If the JoinColumn annotation itself is defaulted, a single join column is assumed and the default values apply. Example: @ManyToOne ... @JoinColumn(name="CUST_ID") // join column is in table for Order public Set


) Specifies a mapping to an entity that is a map key. The map key join column is in the collection table ... annotation is specified, a single join column is assumed and the default values apply. Example 1 ... ", joinColumns=@JoinColumn(name="STORE")) @Column(name="COPIES_IN_STOCK") @MapKeyJoinColumn(name

Getting Started

ObjectDB is very easy to use. Follow the Getting Started Tutorial and the Quick Tour manual chapter and in minutes you may be able to write and run first Java programs against ObjectDB.

Prior knowledge or experience in database programming (SQL, JDBC, ORM, JPA, etc.) is not required, but some background in using the Java language is essential.

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