What are the SQL expressions used in ArcGIS?
A SQL expression contains a combination of one or more values, operators, and SQL functions that can be used to query or select a subset of features and table records within ArcGIS. All SQL queries are expressed using the keyword SELECT.
Can you use distinct order in an ArcGIS query?
Because you are selecting columns as a whole, you cannot restrict the SELECT to return only some of the columns in the corresponding table because the SELECT * syntax is hard-coded. For this reason, keywords, such as DISTINCT, ORDER BY, and GROUP BY, cannot be used in an SQL expression in ArcGIS except when using subqueries.
When do you use field types in ArcGIS?
For instance, when configuring a filter, the field type you choose determines the operators that display, which in turn impacts the values you can include in your filter condition. The following table describes the available field types: A field type that guarantees a unique ID for each row of data.
When to use the not equal keyword in ArcGIS?
The not equal (<>) operator can also be used when querying strings. If the string contains a single quote you will first need to use another single quote as an escape character. For example: You can use the NULL keyword to select features and records that have null values for the specified field.
When to use upper or lower function in ArcGIS?
For file-based data sources such as file geodatabases or shapefiles, you can use the UPPER or LOWER function to set the case for a selection. For example, the following expression selects the state whose name is stored as ‘Rhode Island’ or ‘RHODE ISLAND’:
When to use the not equal operator in ArcGIS?
The not equal (<>) operator can also be used when querying strings. If the string contains a single quote you will first need to use another single quote as an escape character. For example: You can use the NULL keyword to select features and records that have null values for the specified field. The NULL keyword is always preceded by IS or IS NOT.
How are wildcards used in ArcSDE query builder?
The wildcards above work for any file-based data or ArcSDE geodatabase. The wildcards you use to query personal geodatabases are * for any number of characters and ? for one character. Wildcard characters appear as buttons on the Select by Attributes and Query Builder dialog boxes.