Dql to update

You are commenting using your Google account. You are commenting using your Twitter account. You are commenting using your Facebook account. Notify me of new comments via email. Notify me of new posts via email. Skip to content. Share this: Reddit. Like this: Like Loading Hi Ajith, Could you pl. Hello there. Hi Ajith, I have the following query to list all documents and folders in a cabinet.

Hi Ajith Is it possible using DQL query to see whether an attribute name for an object type is a repeating attribute or single attribute? Any suggestions would be helpful.

Be sure toupdate statistics often. If the DBA uses their own scripts to calculate the statistics, then these enhancements will not be available. It is strongly recommended that all indexes on Documentum base tables be created from within Documentum and not at the database level.

This may result in a less efficient SQL query. The syntax for creating new indexes is as follows:. Be sure to create the index on the appropriate type table. This is useful when it is a DQL query that is performing poorly and you wish to test using a nonsuperuser account. Non-query type APIs are not traced. Here is an example of tracing a simple DQL query.

The hint does not affect the execution plan, but may free up database resources more quickly. To fetch all the results, set N to 0.

They are not handled by Content Server. To include a passthrough hint, you must identify the database for which the hint is valid. To identify the target database, keywords precede the hints.

The entire list of hints must be enclosed in parentheses. If the table is registered, check with the owner of the registered table, or a Documentum superuser, about giving you access to the table. DCTM 5. If specified, the method removes all aborted workflows in the repository. You can set this using DA. To deal with apostrophes in DQL, escape with apsotrophe. When Doctrine hydrates a query with fetch-join it returns the class in the FROM clause on the root level of the result array.

In the previous example an array of User instances is returned and the address of each user is fetched and hydrated into the User address variable. If you access the address Doctrine does not need to lazy load the association with another query. Doctrine allows you to walk all the associations between all the objects in your domain model.

Objects that were not already loaded from the database are replaced with lazy load proxy instances. Non-loaded Collections are also replaced by lazy-load instances that fetch all the contained objects upon first access. However relying on the lazy-load mechanism leads to many small queries executed against the database, which can significantly affect the performance of your application.

DQL supports both named and positional parameters, however in contrast to many SQL dialects positional parameters are specified with numbers, for example? Named parameters are specified with :name1, :name2 and so on.

This section contains a large set of DQL queries and some explanations of what is happening. The actual result also depends on the hydration mode. Joins between entities without associations are available, where you can generate an arbitrary join with the following syntax:. With an arbitrary join the result differs from the joins using a mapped property.

The result of an arbitrary join is an one dimensional array with a mix of the entity from the SELECT and the joined entity fitting to the filtering of the query. In case of the example with User and Banlist , it can look like this:.

In this form of join, the Banlist entities found by the filtering in the WITH part are not fetched by an accessor method on User , but are already part of the result. In case the accessor method for Banlists is invoked on a User instance, it loads all the related Banlist objects corresponding to this User.

This change of behaviour needs to be considered when the DQL is switched to an arbitrary join. By default when you run a DQL query in Doctrine and select only a subset of the fields for a given entity, you do not receive objects back.

Instead, you receive only arrays as a flat rectangular result set, similar to how you would if you were just using SQL directly and joining some data. By default a result is incremented by numerical keys starting with 0. However with INDEX BY you can specify any other column to be the key of your result, it really only makes sense with primary or unique fields though:.

You can also index by a to-one association, which will use the id of the associated entity the join column as the key in the result set:. Entities that are already loaded into the persistence context will NOT be synced with the updated database state.

It is recommended to call EntityManager clear and retrieve new instances of any affected entity. Therefore, some limitations apply:. This, however, is costly performance-wise: It means collections and related entities are fetched into memory even if they are marked as lazy. Pulling object graphs into memory on cascade can cause considerable performance overhead, especially when the cascaded collections are large. Make sure to weigh the benefits and downsides.

It is possible to wrap both fields and identification values into aggregation and DQL functions. Numerical fields can be part of computations using mathematical operations. DQL offers a wide-range of additional expressions that are known from SQL, here is a list of all the supported constructs:. By default DQL comes with functions that are part of a large basis of underlying databases.

However you will most likely choose a database platform at the beginning of your project and most likely never change it. For this cases you can easily extend the DQL parser with own specialized platform functions. The functions have to return either a string, numeric or datetime value depending on the registered function type. All the given classes have to implement the base class :.

This section demonstrates how you can query inherited classes and what type of results to expect. Single Table Inheritance is an inheritance mapping strategy where all classes of a hierarchy are mapped to a single database table. In order to distinguish which row represents which type in the hierarchy a so-called discriminator column is used.

First we need to setup an example set of entities to use. In this scenario it is a generic Person and Employee example:. First notice that the generated SQL to create the tables for these entities looks like the following:. Now when persist a new Employee instance it will set the discriminator value for us automatically:.

If we check the generated SQL you will notice it has some special conditions added to ensure that we will only get back Employee entities:. Class Table Inheritance is an inheritance mapping strategy where each class in a hierarchy is mapped to several tables: its own table and the tables of all parent classes.

The table of a child class is linked to the table of a parent class through a foreign key constraint. Doctrine ORM implements this strategy through the use of a discriminator column in the topmost table of the hierarchy because this is the easiest way to achieve polymorphic queries with Class Table Inheritance.

Now take a look at the SQL which is generated to create the table, you'll notice some differences:. Here are some examples:. A hydration mode specifies a particular way in which a SQL result set is transformed. Each hydration mode has its own dedicated method on the Query class. Here they are:. Using this method you can directly supply the hydration mode as the second parameter via one of the Query constants.