Class SQLServerDialect

Direct Known Subclasses:
JTDSSQLServerDialect

public class SQLServerDialect extends BasicSQLDialect
Dialect implementation for Microsoft SQL Server.
Author:
Justin Deoliveira, OpenGEO
  • Constructor Details

    • SQLServerDialect

      public SQLServerDialect(JDBCDataStore dataStore)
  • Method Details

    • includeTable

      public boolean includeTable(String schemaName, String tableName, Connection cx) throws SQLException
      Description copied from class: SQLDialect
      Determines if the specified table should be included in those published by the datastore.

      This method returns true if the table should be published as a feature type, otherwise it returns false. Subclasses should override this method, this default implementation returns true.

      A database connection is provided to the dialect but it should not be closed. However any statements objects or result sets that are instantiated from it must be closed.

      Overrides:
      includeTable in class SQLDialect
      Parameters:
      schemaName - The schema of the table, might be null..
      tableName - The name of the table.
      cx - Database connection.
      Throws:
      SQLException
    • getGeometryTypeName

      public String getGeometryTypeName(Integer type)
      Description copied from class: SQLDialect
      Returns the name of a geometric type based on its integer constant.

      The constant, type, is registered in SQLDialect.registerSqlTypeNameToClassMappings(Map).

      This default implementation returns null, subclasses should override.

      Overrides:
      getGeometryTypeName in class SQLDialect
    • registerClassToSqlMappings

      public void registerClassToSqlMappings(Map<Class<?>,Integer> mappings)
      Description copied from class: SQLDialect
      Registers the java type to sql type mappings that the datastore uses when reading and writing objects to and from the database. *

      Subclasses should extend (not override) this method to provide additional mappings, or to override mappings provided by this implementation. This implementation provides the following mappings:

      Overrides:
      registerClassToSqlMappings in class SQLDialect
    • registerSqlTypeNameToClassMappings

      public void registerSqlTypeNameToClassMappings(Map<String,Class<?>> mappings)
      Description copied from class: SQLDialect
      Registers the sql type name to java type mappings that the dialect uses when reading and writing objects to and from the database.

      Subclasses should extend (not override) this method to provide additional mappings, or to override mappings provided by this implementation. This implementation provides the following mappings:

      Overrides:
      registerSqlTypeNameToClassMappings in class SQLDialect
    • registerSqlTypeToSqlTypeNameOverrides

      public void registerSqlTypeToSqlTypeNameOverrides(Map<Integer,String> overrides)
      Description copied from class: SQLDialect
      Registers any overrides that should occur when mapping an integer sql type value to an underlying sql type name.

      The default implementation of this method does nothing. Subclasses should override in cases where:

      • database type metadata does not provide enough information to properly map
      • to support custom types (those not in Types)
      Overrides:
      registerSqlTypeToSqlTypeNameOverrides in class SQLDialect
    • postCreateTable

      public void postCreateTable(String schemaName, SimpleFeatureType featureType, Connection cx) throws SQLException, IOException
      Description copied from class: SQLDialect
      Callback to execute any additional sql statements post a create table statement.

      This method should be implemented by subclasses that need to do some post processing on the database after a table has been created. Examples might include:

      • Creating a sequence for a primary key
      • Registering geometry column metadata
      • Creating a spatial index

      A common case is creating an auto incrementing sequence for the primary key of a table. It should be noted that all tables created through the datastore use the column "fid" as the primary key.

      A direct connection to the database is provided (cx). This connection must not be closed, however any statements or result sets instantiated from the connection must be closed.

      Overrides:
      postCreateTable in class SQLDialect
      Parameters:
      schemaName - The name of the schema, may be null.
      featureType - The feature type that has just been created on the database.
      cx - Database connection.
      Throws:
      SQLException
      IOException
    • getMapping

      public Class<?> getMapping(ResultSet columnMetaData, Connection cx) throws SQLException
      Description copied from class: SQLDialect
      Determines the class mapping for a particular column of a table.

      Implementing this method is optional. It is used to allow database to perform custom type mappings based on various column metadata. It is called before the mappings registered in SQLDialect.registerSqlTypeToClassMappings(Map) and are used to determine the mapping. Subclasses should implement as needed, this default implementation returns <code>null</code>. </p> <p> The <tt>columnMetaData</tt> argument is provided from {@link DatabaseMetaData#getColumns(String, String, String, String)}. </p>

      Overrides:
      getMapping in class SQLDialect
      Parameters:
      columnMetaData - The column metadata
      cx - The connection used to retrieve the metadata
      Returns:
      The class mapped to the to column, or null.
      Throws:
      SQLException
    • getGeometrySRIDfromMetadataTable

      public Integer getGeometrySRIDfromMetadataTable(String schemaName, String tableName, String columnName, Connection cx) throws SQLException
      Throws:
      SQLException
    • getGeometrySRID

      public Integer getGeometrySRID(String schemaName, String tableName, String columnName, Connection cx) throws SQLException
      Description copied from class: SQLDialect
      Returns the spatial reference system identifier (srid) for a particular geometry column.

      This method is given a direct connection to the database. The connection must not be closed. However any statements or result sets instantiated from the connection must be closed.

      In the event that the srid cannot be determined, this method should return null .

      Overrides:
      getGeometrySRID in class SQLDialect
      Parameters:
      schemaName - The database schema, could be null.
      tableName - The table, never null.
      columnName - The column name, never null
      cx - The database connection.
      Throws:
      SQLException
    • getGeometryDimensionFromMetadataTable

      public Integer getGeometryDimensionFromMetadataTable(String schemaName, String tableName, String columnName, Connection cx) throws SQLException
      Throws:
      SQLException
    • getGeometryDimension

      public int getGeometryDimension(String schemaName, String tableName, String columnName, Connection cx) throws SQLException
      Description copied from class: SQLDialect
      Returns the dimension of the coordinates in the geometry. Defaults to 2, subclasses can override it.

      This method is given a direct connection to the database. The connection must not be closed. However any statements or result sets instantiated from the connection must be closed.

      In the event that the dimension cannot be determined, this method should return 2

      Overrides:
      getGeometryDimension in class SQLDialect
      Parameters:
      schemaName - The database schema, could be null.
      tableName - The table, never null.
      columnName - The column name, never null
      cx - The database connection.
      Throws:
      SQLException
    • encodeGeometryColumn

      public void encodeGeometryColumn(GeometryDescriptor gatt, String prefix, int srid, Hints hints, StringBuffer sql)
      Description copied from class: SQLDialect
      Encodes the name of a geometry column in a SELECT statement.

      This method should wrap the column name in any functions that are used to retrieve its value. For instance, often it is necessary to use the function asText, or asWKB when fetching a geometry.

      This method must also be sure to properly encode the name of the column with the SQLDialect.encodeColumnName(String, String, StringBuffer) function.

      Example:

         
         sql.append( "asText(" );
         column( gatt.getLocalName(), sql );
         sql.append( ")" );
         
       
      Overrides:
      encodeGeometryColumn in class SQLDialect
    • encodeGeometryValue

      public void encodeGeometryValue(Geometry value, int dimension, int srid, StringBuffer sql) throws IOException
      Description copied from class: BasicSQLDialect
      Encodes a geometry value in an sql statement.

      An implementations should serialize value into some exchange format which will then be transported to the underlying database. For example, consider an implementation which converts a geometry into its well known text representation:

         
         sql.append( "GeomFromText('" );
         sql.append( new WKTWriter().write( value ) );
         sql.append( ")" );
         
        

      The srid parameter is the spatial reference system identifier of the geometry, or 0 if not known.

      Attention should be paid to emtpy geometries (g.isEmtpy() == true) as they cannot be encoded in WKB and several databases fail to handle them property. Common treatment is to equate them to NULL

      Specified by:
      encodeGeometryValue in class BasicSQLDialect
      Throws:
      IOException
    • decodeGeometryValue

      public Geometry decodeGeometryValue(GeometryDescriptor descriptor, ResultSet rs, String column, GeometryFactory factory, Connection cx, Hints hints) throws IOException, SQLException
      Description copied from class: SQLDialect
      Decodes a geometry value from the result of a query.

      This method is given direct access to a result set. The column parameter is the index into the result set which contains the geometric value.

      An implementation should deserialize the value provided by the result set into Geometry object. For example, consider an implementation which deserializes from well known text:

         String wkt = rs.getString( column );
         if ( wkt == null ) {
           return null;
         }
         return new WKTReader(factory).read( wkt );
         
      Note that implementations must handle null values.

      The factory parameter should be used to instantiate any geometry objects.

      Specified by:
      decodeGeometryValue in class SQLDialect
      Throws:
      IOException
      SQLException
    • encodeGeometryEnvelope

      public void encodeGeometryEnvelope(String tableName, String geometryColumn, StringBuffer sql)
      Description copied from class: SQLDialect
      Encodes the spatial extent function of a geometry column in a SELECT statement.

      This method must also be sure to properly encode the name of the column with the #encodeColumnName(String, StringBuffer) function.

      Specified by:
      encodeGeometryEnvelope in class SQLDialect
    • decodeGeometryEnvelope

      public Envelope decodeGeometryEnvelope(ResultSet rs, int column, Connection cx) throws SQLException, IOException
      Description copied from class: SQLDialect
      Decodes the result of a spatial extent function in a SELECT statement.

      This method is given direct access to a result set. The column parameter is the index into the result set which contains the spatial extent value. The query for this value is build with the SQLDialect.encodeGeometryEnvelope(String, String, StringBuffer) method.

      This method must not read any other objects from the result set other then the one referenced by column.

      Specified by:
      decodeGeometryEnvelope in class SQLDialect
      Parameters:
      rs - A result set
      column - Index into the result set which points at the spatial extent value.
      cx - The database connection.
      Throws:
      SQLException
      IOException
    • createFilterToSQL

      public FilterToSQL createFilterToSQL()
      Description copied from class: BasicSQLDialect
      Creates the filter encoder to be used by the datastore when encoding query predicates.

      Sublcasses can override this method to return a subclass of FilterToSQL if need be.

      Overrides:
      createFilterToSQL in class BasicSQLDialect
    • encodeTableName

      protected void encodeTableName(String schemaName, String tableName, StringBuffer sql, boolean escape)
    • isLimitOffsetSupported

      public boolean isLimitOffsetSupported()
      Description copied from class: SQLDialect
      Returns true if this dialect can encode both Query.getStartIndex() and Query.getMaxFeatures() into native SQL.
      Overrides:
      isLimitOffsetSupported in class SQLDialect
    • applyLimitOffset

      public void applyLimitOffset(StringBuffer sql, int limit, int offset)
      Description copied from class: SQLDialect
      Alters the query provided so that limit and offset are natively dealt with. This might mean simply appending some extra directive to the query, or wrapping it into a bigger one.
      Overrides:
      applyLimitOffset in class SQLDialect
    • encodeValue

      public void encodeValue(Object value, Class type, StringBuffer sql)
      Description copied from class: BasicSQLDialect
      Encodes a value in an sql statement.

      Subclasses may wish to override or extend this method to handle specific types. This default implementation does the following:

      1. The value is encoded via its Object.toString() representation.
      2. If type is a character type (extends CharSequence), it is wrapped in single quotes (').
      Overrides:
      encodeValue in class BasicSQLDialect
    • getGeometryMetadataTable

      public String getGeometryMetadataTable()
      The geometry metadata table in use, if any
    • setGeometryMetadataTable

      public void setGeometryMetadataTable(String geometryMetadataTable)
      Sets the geometry metadata table
    • setUseOffSetLimit

      public void setUseOffSetLimit(Boolean useOffsetLimit)
      Sets whether to use offset limit or not
    • setUseNativeSerialization

      public void setUseNativeSerialization(Boolean useNativeSerialization)
      Sets whether to use native SQL Server binary serialization or WKB serialization
    • setForceSpatialIndexes

      public void setForceSpatialIndexes(boolean forceSpatialIndexes)
      Sets whether to force the usage of spatial indexes by including a WITH INDEX hint
    • setTableHints

      public void setTableHints(String tableHints)
      Sets a comma separated list of table hints that will be added to every select query
    • dropIndex

      public void dropIndex(Connection cx, SimpleFeatureType schema, String databaseSchema, String indexName) throws SQLException
      Drop the index. Subclasses can override to handle extra syntax or db specific situations
      Overrides:
      dropIndex in class SQLDialect
      Throws:
      SQLException
    • postCreateFeatureType

      public void postCreateFeatureType(SimpleFeatureType featureType, DatabaseMetaData md, String databaseSchema, Connection cx) throws SQLException
      Description copied from class: SQLDialect
      Callback which executes after a feature type has been built from a database table.

      This base implementation does nothing, subclasses should override as need be.

      Overrides:
      postCreateFeatureType in class SQLDialect
      Parameters:
      featureType - The build feature type.
      md - The database metadata.
      databaseSchema - The name of the database scheam containing the table containing the column
      cx - The database connection.
      Throws:
      SQLException
    • handleSelectHints

      public void handleSelectHints(StringBuffer sql, SimpleFeatureType featureType, Query query)
      Description copied from class: SQLDialect
      Used to apply search hints on the fully generated SQL (complete of select, from, where, sort, limit/offset)
      Overrides:
      handleSelectHints in class SQLDialect
    • lookupGeneratedValuesPostInsert

      public boolean lookupGeneratedValuesPostInsert()
      Description copied from class: SQLDialect
      Controls whether keys are looked up post or pre insert.

      When a row is inserted into a table, and a key is automatically generated it can be looked up before the insert occurs, or after the insert has been made. Returning false will cause the lookup to occur before the insert via SQLDialect.getNextAutoGeneratedValue(String, String, String, Connection). Returning true will cause the lookup to occur after the insert via SQLDialect.getLastAutoGeneratedValue(String, String, String, Connection).

      Subclasses returning false should implement:

      Subclasses returning true should implement:

      Overrides:
      lookupGeneratedValuesPostInsert in class SQLDialect
    • getLastAutoGeneratedValue

      public Object getLastAutoGeneratedValue(String schemaName, String tableName, String columnName, Connection cx, Statement st) throws SQLException
      Description copied from class: SQLDialect
      Obtains the last value of an auto generated column.

      This method is only called when SQLDialect.lookupGeneratedValuesPostInsert() returns true. Implementations should determine the previous value of a column for which was automatically generated by the database.

      This method is given a direct connection to the database, but this connection should never be closed. However any statements or result sets instantiated from the connection must be closed.

      Implementations should handle the case where schemaName is null.

      Overrides:
      getLastAutoGeneratedValue in class SQLDialect
      Parameters:
      schemaName - The schema name, this might be null.
      tableName - The name of the table.
      columnName - The column.
      cx - The database connection.
      st - The statement used for the insert
      Returns:
      The previous value of the column, or null.
      Throws:
      SQLException
    • registerAggregateFunctions

      public void registerAggregateFunctions(Map<Class<? extends FeatureVisitor>,String> aggregates)
      Description copied from class: SQLDialect
      Registers the set of aggregate functions the dialect is capable of handling.

      Aggregate functions are handled via visitors of special types. The aggregates maps the class of the visitor to the associated function name. This base implementation handles some of the well known mappings:

      Subclasses should extend (not override) to provide additional functions.
      Overrides:
      registerAggregateFunctions in class SQLDialect
    • canGroupOnGeometry

      public boolean canGroupOnGeometry()
      Description copied from class: SQLDialect
      Returns true if this database can "group by" on a Geometry column. Defaults to false, specific implementations with this capability should override
      Overrides:
      canGroupOnGeometry in class SQLDialect
    • encodeNextSequenceValue

      public String encodeNextSequenceValue(String schemaName, String sequenceName)
      Description copied from class: SQLDialect
      Encodes how to get the next sequence value from the DB.

      Implementations should handle the case where schemaName is null.

      Overrides:
      encodeNextSequenceValue in class SQLDialect
    • getNextSequenceValue

      public Object getNextSequenceValue(String schemaName, String sequenceName, Connection cx) throws SQLException
      Description copied from class: SQLDialect
      Obtains the next value of a sequence, incrementing the sequence to the next state in the process.

      Implementations should determine the next value of a column for which values are automatically generated by the database.

      This method is given a direct connection to the database, but this connection should never be closed. However any statements or result sets instantiated from the connection must be closed.

      Implementations should handle the case where schemaName is null.

      Overrides:
      getNextSequenceValue in class SQLDialect
      Parameters:
      schemaName - The schema name, this might be null.
      sequenceName - The name of the sequence.
      cx - The database connection.
      Returns:
      The next value of the sequence, or null.
      Throws:
      SQLException
    • getOptimizedBounds

      public List<ReferencedEnvelope> getOptimizedBounds(String schema, SimpleFeatureType featureType, Connection cx) throws SQLException
      Returns the optimized bounds for the geometry columns of the given feature type. The bounds are extracted from the spatial indexes, if any. This method is enabled by setting the estimatedExtentsEnabled property to true.
      Overrides:
      getOptimizedBounds in class SQLDialect
      Parameters:
      schema - The database schema, if any, or null
      featureType - The feature type containing the geometry columns whose bounds need to computed. Mind, it may be retyped and thus contain less geometry columns than the table
      cx - The connection to the database
      Returns:
      A list of ReferencedEnvelope, one for each geometry column of the feature type, or null if no bounds could be extracted from the spatial indexes
      Throws:
      SQLException - If there is a problem querying the database
    • isEstimatedExtentsEnabled

      public boolean isEstimatedExtentsEnabled()
    • setEstimatedExtentsEnabled

      public void setEstimatedExtentsEnabled(boolean estimatedExtentsEnabled)