During validation, ArcGIS attempts to identify a single unique identifier column for the table. If it finds a qualifying column, you can use that for the query layer. If it cannot find a unique identifier or you want to use a different unique identifier, you can define that in the next p...
Given a group G,we say that a base table A is in the schema of G if A.X is in the schema of G for some attribute X of A. Then cucard(A.X) denotes the unique cardinality of a column A.X in G, cucard(A) in G denotes the maximum value of cucard(A.X) over all attribute...
A query makes it easier to view, add, delete, or change data in your Access desktop database. Queries are also useful when you want to find specific data quickly, calculate or summarize data, or automate data management tasks, such as reviewing the most curr...
What data types are returned? How long are the strings in each column returned? Systems might have very small default and benefit from tuning. For example: Oracle’s defaultfetchSizeis 10. Increasing it to 100 reduces the number of total queries that need to be executed by a factor of 10...
QueryResult queryResult = new QueryResult(); // Create a connection to the database. using (OleDbConnection connection = new OleDbConnection(connectionString)) { // Open the database connection. connection.Open(); List<Column> columns = new...
Retrieving A Single Row / Column From A TableIf you just need to retrieve a single row from the database table, you may use the first method. This method will return a single StdClass object:1$user = DB::table('users')->where('name', 'John')->first(); 2 3echo $user->name;...
Retrieving A Single Row / Column From A TableIf you just need to retrieve a single row from the database table, you may use the first method. This method will return a single StdClass object:1$user = DB::table('users')->where('name', 'John')->first(); 2 3echo $user->name;...
The result of the query looks like this in the data grid: For more information about the union option, see Union Your Data. Change the data type of a field to do a cross-database join When you want to perform a join between two tables in the physical layer of the canvas, the data...
What data types are returned? How long are the strings in each column returned? Systems might have very small default and benefit from tuning. For example: Oracle’s defaultfetchSizeis 10. Increasing it to 100 reduces the number of total queries that need to be executed by a factor of 10...
DFEPipelineRangeCount – Counts the number of solutions matching a given pattern, and returns a single solution containing the count value. DFEPipelineScan – Scans the database for the given pattern argument, with or without a given filter on column(s). ...