MySQLDialect (Geotools modules 28-SNAPSHOT API)

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 Summary

Fields
Modifier and Type	Field and Description
`protected Integer`	`GEOMETRY`
`protected boolean`	`isMySqlVersion80OrAbove` flag indicating we are using MySQL v8.0 or higher.
`protected Integer`	`LINESTRING`
`protected Integer`	`MULTILINESTRING`
`protected Integer`	`MULTIPOINT`
`protected Integer`	`MULTIPOLYGON`
`protected Integer`	`POINT` mysql spatial types
`protected Integer`	`POLYGON`
`protected String`	`storageEngine` the storage engine to use when creating tables, one of MyISAM, InnoDB
`protected boolean`	`usePreciseSpatialOps` flag that indicates that precise spatial operation should be used (should apply to MySQL versions 5.6 and above)

Fields inherited from class SQLDialect
BASE_DBMS_CAPABILITIES, dataStore, forceLongitudeFirst, LOGGER

Constructor Summary

Constructors
Constructor and Description

MySQLDialect(JDBCDataStore dataStore)

Constructors
Constructor and Description
`MySQLDialect(JDBCDataStore dataStore)`

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`applyLimitOffset(StringBuffer sql, int limit, int offset)` Alters the query provided so that limit and offset are natively dealt with.
`boolean`	`canGroupOnGeometry()` Returns true if this database can "group by" on a Geometry column.
`Envelope`	`decodeGeometryEnvelope(ResultSet rs, int column, Connection cx)` Decodes the result of a spatial extent function in a SELECT statement.
`Geometry`	`decodeGeometryValue(GeometryDescriptor descriptor, ResultSet rs, String name, GeometryFactory factory, Connection cx, Hints hints)` Decodes a geometry value from the result of a query.
`void`	`dropIndex(Connection cx, SimpleFeatureType schema, String databaseSchema, String indexName)` Drop the index.
`void`	`encodeGeometryColumn(GeometryDescriptor gatt, String prefix, int srid, Hints hints, StringBuffer sql)` Encodes the name of a geometry column in a SELECT statement.
`void`	`encodeGeometryEnvelope(String tableName, String geometryColumn, StringBuffer sql)` Encodes the spatial extent function of a geometry column in a SELECT statement.
`void`	`encodePostColumnCreateTable(AttributeDescriptor att, StringBuffer sql)` Encodes anything post a column in a CREATE TABLE statement.
`void`	`encodePostCreateTable(String tableName, StringBuffer sql)` Encodes anything post a CREATE TABLE statement.
`void`	`encodePrimaryKey(String column, StringBuffer sql)` Encodes the primary key definition in a CREATE TABLE statement.
`Integer`	`getGeometrySRID(String schemaName, String tableName, String columnName, Connection cx)` Returns the spatial reference system identifier (srid) for a particular geometry column.
`String`	`getGeometryTypeName(Integer type)` Returns the name of a geometric type based on its integer constant.
`Object`	`getLastAutoGeneratedValue(String schemaName, String tableName, String columnName, Connection cx)` Obtains the last value of an auto generated column.
`String`	`getNameEscape()` Returns the string used to escape names.
`String`	`getStorageEngine()`
`boolean`	`getUsePreciseSpatialOps()`
`boolean`	`includeTable(String schemaName, String tableName, Connection cx)` Determines if the specified table should be included in those published by the datastore.
`boolean`	`isLimitOffsetSupported()` Returns true if this dialect can encode both Query.getStartIndex() and Query.getMaxFeatures() into native SQL.
`boolean`	`isMySqlVersion80OrAbove()`
`boolean`	`lookupGeneratedValuesPostInsert()` Controls whether keys are looked up post or pre insert.
`void`	`postCreateTable(String schemaName, SimpleFeatureType featureType, Connection cx)` Callback to execute any additional sql statements post a create table statement.
`void`	`registerClassToSqlMappings(Map<Class<?>,Integer> mappings)` 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.
`void`	`registerSqlTypeNameToClassMappings(Map<String,Class<?>> mappings)` Registers the sql type name to java type mappings that the dialect uses when reading and writing objects to and from the database.
`void`	`registerSqlTypeToClassMappings(Map<Integer,Class<?>> mappings)` Registers the sql type to java type mappings that the dialect uses when reading and writing objects to and from the database.
`void`	`registerSqlTypeToSqlTypeNameOverrides(Map<Integer,String> overrides)` Registers any overrides that should occur when mapping an integer sql type value to an underlying sql type name.
`void`	`setMySqlVersion80OrAbove(boolean mySqlVersion80OrAbove)`
`void`	`setStorageEngine(String storageEngine)`
`void`	`setUsePreciseSpatialOps(boolean usePreciseSpatialOps)`

Methods inherited from class SQLDialect
addSupportedHints, canSimplifyPoints, convertValue, createCRS, createIndex, decodeGeometryValue, encodeColumnAlias, encodeColumnName, encodeColumnType, encodeCreateTable, encodeGeometryColumnGeneralized, encodeGeometryColumnSimplified, encodeJoin, encodeNextSequenceValue, encodePostSelect, encodeSchemaName, encodeTableAlias, encodeTableName, escapeName, getAggregateConverter, getDefaultVarcharSize, getDesiredTablesType, getGeometryDimension, getIndexes, getLastAutoGeneratedValue, getMapping, getNextAutoGeneratedValue, getNextSequenceValue, getOptimizedBounds, getPkColumnValue, getPrimaryKey, getRestrictions, getResultTypes, getSequenceForColumn, getSQLType, handleSelectHints, handleUserDefinedType, initializeConnection, isAggregatedSortSupported, isArray, isAutoCommitQuery, isGroupBySupported, ne, postCreateAttribute, postCreateFeatureType, postDropTable, preDropTable, registerAggregateFunctions, splitFilter, supportsSchemaForIndex

Methods inherited from class Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - 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 Detail
  - MySQLDialect
```
public MySQLDialect(JDBCDataStore dataStore)
```
- Method Detail
  - 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: SQLDialect.getNextAutoGeneratedValue(String, String, String, Connection) Subclasses returning true should implement: SQLDialect.getLastAutoGeneratedValue(String, String, String, Connection) 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

Class MySQLDialect

Field Summary

Fields inherited from class SQLDialect

Constructor Summary

Method Summary

Methods inherited from class SQLDialect

Methods inherited from class Object

Field Detail

POINT

LINESTRING

POLYGON

MULTIPOINT

MULTILINESTRING

MULTIPOLYGON

GEOMETRY

storageEngine

usePreciseSpatialOps

isMySqlVersion80OrAbove

Constructor Detail

MySQLDialect

Method Detail

setStorageEngine

getStorageEngine

setUsePreciseSpatialOps

getUsePreciseSpatialOps

isMySqlVersion80OrAbove

setMySqlVersion80OrAbove

includeTable

getNameEscape

getGeometryTypeName

getGeometrySRID

encodeGeometryColumn

encodeGeometryEnvelope

decodeGeometryEnvelope

decodeGeometryValue

registerClassToSqlMappings

registerSqlTypeToClassMappings

registerSqlTypeNameToClassMappings

registerSqlTypeToSqlTypeNameOverrides

encodePostCreateTable

encodePostColumnCreateTable

postCreateTable

encodePrimaryKey

lookupGeneratedValuesPostInsert

getLastAutoGeneratedValue

isLimitOffsetSupported

applyLimitOffset

dropIndex

canGroupOnGeometry