Class MySQLDialect

Object
SQLDialect
MySQLDialect

public class MySQLDialect extends SQLDialect
Delegate for MySQLDialectBasic and MySQLDialectPrepared which implements the common part of the api.
Author:
Justin Deoliveira, OpenGEO
  • Field Details

    • POINT

      protected Integer POINT
      mysql spatial types
    • LINESTRING

      protected Integer LINESTRING
    • POLYGON

      protected Integer POLYGON
    • MULTIPOINT

      protected Integer MULTIPOINT
    • MULTILINESTRING

      protected Integer MULTILINESTRING
    • MULTIPOLYGON

      protected Integer MULTIPOLYGON
    • GEOMETRY

      protected Integer GEOMETRY
    • storageEngine

      protected String storageEngine
      the storage engine to use when creating tables, one of MyISAM, InnoDB
    • usePreciseSpatialOps

      protected boolean usePreciseSpatialOps
      flag that indicates that precise spatial operation should be used (should apply to MySQL versions 5.6 and above)
    • isMySqlVersion80OrAbove

      protected boolean isMySqlVersion80OrAbove
      flag indicating we are using MySQL v8.0 or higher.
  • Constructor Details

  • Method Details

    • setStorageEngine

      public void setStorageEngine(String storageEngine)
    • getStorageEngine

      public String getStorageEngine()
    • setUsePreciseSpatialOps

      public void setUsePreciseSpatialOps(boolean usePreciseSpatialOps)
    • getUsePreciseSpatialOps

      public boolean getUsePreciseSpatialOps()
    • isMySqlVersion80OrAbove

      public boolean isMySqlVersion80OrAbove()
    • setMySqlVersion80OrAbove

      public void setMySqlVersion80OrAbove(boolean mySqlVersion80OrAbove)
    • 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
    • getNameEscape

      public String getNameEscape()
      Description copied from class: SQLDialect
      Returns the string used to escape names.

      This value is used to escape any name in a query. This includes columns, tables, schemas, indexes, etc... If no escape is necessary this method should return the empty string, and never return null.

      This default implementation returns a single double quote ("), subclasses must override to provide a different espcape.

      Overrides:
      getNameEscape in class SQLDialect
    • 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
    • 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
    • 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
    • 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
    • decodeGeometryValue

      public Geometry decodeGeometryValue(GeometryDescriptor descriptor, ResultSet rs, String name, 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
    • 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
    • registerSqlTypeToClassMappings

      public void registerSqlTypeToClassMappings(Map<Integer,Class<?>> mappings)
      Description copied from class: SQLDialect
      Registers the sql type 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:
      registerSqlTypeToClassMappings 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
    • encodePostCreateTable

      public void encodePostCreateTable(String tableName, StringBuffer sql)
      Description copied from class: SQLDialect
      Encodes anything post a CREATE TABLE statement.

      This is appended to a CREATE TABLE statement after the column definitions. This default implementation does nothing, subclasses should override as need be.

      Overrides:
      encodePostCreateTable in class SQLDialect
    • encodePostColumnCreateTable

      public void encodePostColumnCreateTable(AttributeDescriptor att, StringBuffer sql)
      Description copied from class: SQLDialect
      Encodes anything post a column in a CREATE TABLE statement.

      This is appended after the column name and type. Subclasses may choose to override this method, the default implementation does nothing.

      Overrides:
      encodePostColumnCreateTable in class SQLDialect
      Parameters:
      att - The attribute corresponding to the column.
    • 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
    • encodePrimaryKey

      public void encodePrimaryKey(String column, StringBuffer sql)
      Description copied from class: SQLDialect
      Encodes the primary key definition in a CREATE TABLE statement.

      Subclasses should override this method if need be, the default implementation does the following:

         
         encodeColumnName( column, sql );
         sql.append( " int PRIMARY KEY" );
         
       
      Overrides:
      encodePrimaryKey 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) 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.
      Returns:
      The previous value of the column, or null.
      Throws:
      SQLException
    • 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
    • dropIndex

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