ArxQueryExpression

Definition

Namespace

ARX.SDK.Query

Package

ARX.SDK

public class ArxQueryExpression

Constructor

• ArxQueryExpression()

  A query with no row source yet: set EntityName or Source.

• ArxQueryExpression(string entityName)

  A query on a table or view (optionally schema-qualified: reporting.v_sales).

  Parameter	Type	Description
  entityName	string	The table or view to read (on PostgreSQL also a materialized view), or schema.name.

• ArxQueryExpression(ArxRowSource source)

  A query on any row source: a table, a view, or a function returning rows (Function).

  Parameter	Type	Description
  source	ArxRowSource	What to read from: a table by name, or a function with its arguments.

Properties

• ArxRowSource Source { get; set; }

  What the query reads from.

• string EntityName { get; set; }

  The row source's name. Setting it makes the source that table or view.

• bool Distinct { get; set; }

  SELECT DISTINCT: rows that differ in no selected column come back once. A distinct (or aggregate) query doesn't add the id to the columns, since it would make every row distinct, so its rows have no ArxEntity.RecordId: select the id column if you need it.

• int? Top { get; set; }

  At most this many rows (LIMIT), without paging. Can't be combined with PageInfo (ARX1001).

• ArxColumnSet ColumnSet { get; set; }

  The columns to read. Empty (the default) or AllColumns reads every column. A column can be written column._lk.table.column1,column2 to join a referenced table directly.

• ArxFilterExpression Criteria { get; set; }

  The conditions rows have to meet (nested And/Or).

• List<ArxOrderExpression> Orders { get; set; }

  The sort keys, in order; AddOrder adds one.

• List<ArxLinkEntity> LinkEntities { get; set; }

  The joins; AddLink adds one.

• ArxPagingInfo? PageInfo { get; set; }

  Offset paging: the page size and number, and whether to return the total (in the same round trip).

• ArxAggregateInfo? AggregateInfo { get; set; }

  Aggregates and group by; null for a plain read.

Methods

• void AddOrder(string attributeName, ArxOrderType orderType)

  Orders the results by an attribute; call again for the next key.

  Parameter	Type	Description
  attributeName	string	The column to order by.
  orderType	ArxOrderType	Ascending or Descending.

• void AddOrder(string entityAlias, string attributeName, ArxOrderType orderType)

  Orders by a column of a joined entity, named by its alias.

  Parameter	Type	Description
  entityAlias	string	The link alias the column belongs to.
  attributeName	string	The column to order by.
  orderType	ArxOrderType	Ascending or Descending.

• ArxLinkEntity AddLink(string linkToEntityName, string linkFromAttributeName, string linkToAttributeName, ArxJoinOperator joinOperator)

  Joins a table (see ArxLinkEntity) and returns the join, to add its columns, alias and criteria.

  Parameter	Type	Description
  linkToEntityName	string	The table to join.
  linkFromAttributeName	string	The column of the query's own table that the join matches.
  linkToAttributeName	string	The column of the joined table that it matches.
  joinOperator	ArxJoinOperator	INNER (rows with a match only) or LEFT (every row, with nulls where nothing matches).

Usage

var query = new ArxQueryExpression("legacy_customer");

Use columns named outside the name rule, through aliases, scenario 2

Used in:

• Use columns named outside the name rule, through aliasesCreate
• Log every call through ILoggerCreate
• Read your own writes in an ARX transactionRetrieve
• Retrieve many records with a queryRetrieveMultiple
• Page through resultsRetrieveMultiple
• Query without a catalogRetrieveMultiple
• A contact search screenRetrieveMultiple
• Accounts and contacts in one queryRetrieveMultiple
• A report: accounts by industryRetrieveMultiple
• Dates and times in conditionsRetrieveMultiple
• Read a viewRetrieveMultiple
• Rows from a function: refused on MySQL, and what to read insteadRetrieveMultiple
• Lookups and display namesRetrieveMultiple
• Turn read errors into messagesRetrieveMultiple
• Catch an SQL injection attempt on a searchRetrieveMultiple
• Read in a batch scopeRetrieveMultiple
• Export a large table in pagesRetrieveMultiple
• A security check around a search endpointRetrieveMultiple
• Filter expressions in depth: nesting, recursion, links, And and OrRetrieveMultiple
• Link entities in depth: chains, branches, criteria per level, recursionRetrieveMultiple
• Paging in depth: the total is opt-in, ask once, load more, Top, seek pagingRetrieveMultiple
• Read other row sources: a view in a schema, a summary view, a table with no idRetrieveMultiple
• Functions in depth on MySQL: tables, procedures and scalar values instead of row sourcesRetrieveMultiple
• Views in depth: computed criteria, links both ways, declared ids and lookups, column boundariesRetrieveMultiple
• Retrieve on a preloaded schema: lookups found, column types, Strict, saved JSONRetrieveMultiple
• Page through a procedure's result: the procedure pages itself, ARX pages a result setExecute
• Execute on a preloaded, Strict schema: routines aren't covered, tables areExecute