ElasticSearch Data Model

Connection String Options

  1. Auto Cache
  2. Batch Size
  3. Cache Connection
  4. Cache Driver
  5. Cache Location
  6. Cache Metadata
  7. Cache Query Result
  8. Connect On Open
  9. Firewall Password
  10. Firewall Port
  11. Firewall Server
  12. Firewall Type
  13. Firewall User
  14. Flatten Arrays
  15. Flatten Objects
  16. Generate Schema Files
  17. Location
  18. Logfile
  19. Max Log File Size
  20. Max Results
  21. Offline
  22. Other
  23. Page Size
  24. Password
  25. Pool Idle Timeout
  26. Pool Max Size
  27. Pool Wait Time
  28. Port
  29. Proxy Auth Scheme
  30. Proxy Auto Detect
  31. Proxy Exceptions
  32. Proxy Password
  33. Proxy Port
  34. Proxy Server
  35. Proxy SSL Type
  36. Proxy User
  37. Pseudo Columns
  38. Query Passthrough
  39. Readonly
  40. Row Scan Depth
  41. RTK
  42. Scroll Duration
  43. Server
  44. SSL Client Cert
  45. SSL Client Cert Password
  46. SSL Client Cert Subject
  47. SSL Client Cert Type
  48. SSL Server Cert
  49. Support Enhanced SQL
  50. Tables
  51. Timeout
  52. Use Connection Pooling
  53. User
  54. Verbosity
  55. Views

Auto Cache

Data Type

bool

Default Value

false

Remarks

When AutoCache is set, the driver automatically maintains a cache of your table's data in the database of your choice. With CacheQueryResult additionally set, the driver updates the cache when you execute a SELECT query and returns the live results from the Elasticsearch data.

 

Explicitly Caching SELECT Results

 

CacheQueryResult is a way to query Elasticsearch in real time while maintaining a cache for offline use. Set CacheQueryResult to update the cache whenever you execute a SELECT statement. When you execute a SELECT statement with AutoCache and CacheQueryResult set, the driver executes the query to the remote data and caches the results; rows that already exist are overwritten. That is, SELECT statements are used to create and refresh the cache, not to query it. Data manipulation commands are executed to the remote data as well.

To query the cached data, set the Offline property. If you need to query the cached data in an online connection, you can append #CACHE to the table name. For example:

SELECT * FROM [Account#CACHE]

 

 

Setting the Caching Database

 

When AutoCache is set, the driver caches to a simple, file-based cache. You can configure its location or cache to a different database with the following properties:

 

 

See Also

 

 

  • CacheQueryResult: Insert or update each row returned into the corresponding table in the cache.
  • Caching: Best Practices: This section provides more examples of using AutoCache with Offline, as well as information on determining a caching strategy.
  • CacheMetadata: This property reduces the amount of metadata that crosses the network by persisting table schemas retrieved from the Elasticsearch metadata. Metadata then needs to be retrieved only once instead of every connection.
  • CACHE Statements: You can use the CACHE statement to persist any SELECT query, as well as manage the cache; for example, refreshing schemas.

 

 

 

Batch Size

Data Type

int

Default Value

0

Remarks

When BatchSize is set to a value greater than 0, the batch operation will split the entire batch into separate batches of size BatchSize. The split batches will then be submitted to the server individually. This is useful when the server has limitations on the size of the request that can be submitted.

Setting BatchSize to 0 will submit the entire batch as specified.

 

Cache Connection

Data Type

string

Default Value

""

Remarks

The cache database is determined based on the CacheDriver and CacheConnection properties. Both properies are required to use the cache database. Examples of common cache database settings can be found below. For more information on setting the caching database's driver, refer to CacheDriver.

The connection string specified in the CacheConnection property is passed directly to the underlying CacheDriver. Consult the documentation for the specific JDBC driver for more information on the available properties. Make sure to include the JDBC driver in your application's classpath.

 

Derby and Java DB

 

The driver simplifies caching to Derby, only requiring you to set the CacheLocation property to make a basic connection.

Alternatively, you can configure the connection to Derby manually using CacheProvider and CacheConnection. Below is the Derby JDBC URL syntax:

jdbc:derby:[subsubprotocol:][databaseName][;attribute=value[;attribute=value] ... ]
For example, to cache to an in-memory database, use the following:
jdbc:derby:memory

 

 

SQLite

 

To cache to SQLite, you can use the SQLite JDBC driver. Below is the syntax of the JDBC URL:

jdbc:sqlite:dataSource
  • Data Source: The path to an SQLite database file. Or, use a value of :memory to cache in memory.

 

 

MySQL

 

The installation includes the CData JDBC Driver for MySQL. Below is an example JDBC URL:

jdbc:mysql:User=root;Password=root;Server=localhost;Port=3306;Database=cache
Below are typical connection properties:

 

 

  • Server: The IP address or domain name of the server you want to connect to.
  • Port: The port that the server is running on.
  • User: The username provided for authentication to the database.
  • Password: The password provided for authentication to the database.
  • Database: The name of the database.
SQL Server

 

The JDBC URL for the Microsoft JDBC Driver for SQL Server has the following syntax:

jdbc:sqlserver://[serverName[\instance][:port]][;database=databaseName][;property=value[;property=value] ... ]
For example:
jdbc:sqlserver://localhost\sqlexpress:1433;integratedSecurity=true
Below are typical SQL Server connection properties:
  • Server: The name or network address of the computer running SQL Server. To connect to a named instance instead of the default instance, this property can be used to specify the host name and the instance, separated by a backslash.
  • Port: The port SQL Server is running on.
  • Database: The name of the SQL Server database.
  • Integrated Security: Set this option to true to use the current Windows account for authentication. Set this option to false if you are setting the User and Password in the connection.

    To use integrated security, you will also need to add sqljdbc_auth.dll to a folder on the Windows system path. This file is located in the auth subfolder of the Microsoft JDBC Driver for SQL Server installation. The bitness of the assembly must match the bitness of your JVM.

  • User: The username provided for authentication with SQL Server. Only needed if you are not using integrated security.
  • Password: The password provided for authentication with SQL Server. Only needed if you are not using integrated security.
Oracle

 

Below is the conventional JDBC URL syntax for the Oracle JDBC Thin driver:

jdbc:oracle:thin:[userId/password]@[//]host[[:port][:sid]]
For example:
jdbc:oracle:thin:scott/tiger@myhost:1521:orcl
Below are typical connection properties:
  • Data Source: The connect descriptor that identifies the Oracle database. This can be a TNS connect descriptor, an Oracle Net Services name that resolves to a connect descriptor, or, after version 11g, an Easy Connect naming (the host name of the Oracle server with an optional port and service name).

  • Password: The password provided for authentication with the Oracle database.
  • User Id: The user Id provided for authentication with the Oracle database.
PostgreSQL

 

Below is the JDBC URL syntax for the official PostgreSQL JDBC driver:

jdbc:postgresql:[//[host[:port]]/]database[[?option=value][[&option=value][&option=value] ... ]]
For example, the following connection string connects to a database on the default host (localhost) and port (5432):
jdbc:postgresql:postgres
Below are typical connection properties:
  • Host: The address of the server hosting the PostgreSQL database.
  • Port: The port used to connect to the server hosting the PostgreSQL database.
  • Database: The name of the database.
  • Username: The user Id provided for authentication with the PostgreSQL database. You can specify this in the JDBC URL with the "user" parameter.
  • Password: The password provided for authentication with the PostgreSQL database.

 

 

Cache Driver

Data Type

string

Default Value

""

Remarks

You can cache to any database for which you have a JDBC driver, including CData JDBC drivers.

The cache database is determined based on the CacheDriver and CacheConnection properties. The CacheDriver is the name of the JDBC driver class that you would like to use to cache data.

Note that you must also add the CacheDriver JAR to the classpath.

The following examples show how to cache to several major databases. Refer to CacheConnection for more information on the JDBC URL syntax and typical connection properties.

Derby and Java DB

 

 

The driver simplifies Derby configuration. Java DB is the Oracle distribution of Derby. The JAR is shipped in the JDK. You can find the JAR, derby.jar, in the db subfolder of the JDK installation. In most caching scenarios, you need to specify only the following, after adding derby.jar to the classpath.

jdbc:elasticsearch:CacheLocation='c:/Temp/cachedir';Server=127.0.0.1;Port=9200;
To customize the Derby JDBC URL, use CacheDriver and CacheConnection. For example, to cache to an in-memory database, use a JDBC URL like the following:
jdbc:elasticsearch:CacheDriver=org.apache.derby.jdbc.EmbeddedDriver;CacheConnection='jdbc:derby:memory';Server=127.0.0.1;Port=9200;
SQLite

 

Below is a JDBC URL for the SQLite JDBC driver:

jdbc:elasticsearch:CacheDriver=org.sqlite.JDBC;CacheConnection='jdbc:sqlite:C:/Temp/sqlite.db';Server=127.0.0.1;Port=9200;
MySQL

 

Below is a JDBC URL for the included CData JDBC Driver for MySQL:

  jdbc:elasticsearch:Cache Driver=cdata.jdbc.mysql.MySQLDriver;Cache Connection='jdbc:mysql:Server=localhost;Port=3306;Database=cache;User=root;Password=123456';Server=127.0.0.1;Port=9200;
  
The CData JDBC Driver for MySQL is located in the lib subfolder of the CData JDBC Driver for Elasticsearch 2017 installation directory.
SQL Server

 

The following JDBC URL uses the Microsoft JDBC Driver for SQL Server:

jdbc:elasticsearch:Cache Driver=com.microsoft.sqlserver.jdbc.SQLServerDriver;Cache Connection='jdbc:sqlserver://localhost\sqlexpress:7437;user=sa;password=123456;databaseName=Cache';Server=127.0.0.1;Port=9200;
Oracle

 

Below is a JDBC URL for the Oracle Thin Client:

jdbc:elasticsearch:Cache Driver=oracle.jdbc.driver.OracleDriver;CacheConnection='jdbc:oracle:thin:scott/tiger@localhost:1521:orcldb';Server=127.0.0.1;Port=9200;
PostgreSQL

 

The following JDBC URL uses the official PostgreSQL JDBC driver:

jdbc:elasticsearch:CacheDriver=org.postgresql.Driver;CacheConnection='jdbc:postgresql://localhost:5433/postgres?user=postgres&password=admin';Server=127.0.0.1;Port=9200;

 

 

Cache Location

Data Type

string

Default Value

""

Remarks

The CacheLocation is a simple, file-based cache. The driver uses Java DB, Oracle's distribution of the Derby database. To cache to Java DB, you will need to add the Java DB JAR to the classpath. The JAR, derby.jar, is shipped in the JDK and located in the db subfolder of the JDK installation.

CacheLocation defaults to the directory specified by the Location setting.

See Also

 

 

  • AutoCache: Set this to implicitly create and maintain a cache for later offline use.
  • CacheMetadata: Set this to persist the Elasticsearch catalog in CacheLocation.

 

 

Cache Metadata

Data Type

bool

Default Value

false

Remarks

-synch -port -rssis As you execute queries with this property set, table metadata in the Elasticsearch catalog are cached to the file store specified by CacheLocation if set or the user's home directory otherwise. A table's metadata will be retrieved only once, when the table is queried for the first time.

When to Use CacheMetadata

 

The driver automatically persists metadata in memory for up to two hours when you first discover the metadata for a table or view and therefore, CacheMetadata is generally not required. CacheMetadata becomes useful when metadata operations are expensive such as when you are working with large amounts of metadata or when you have many short-lived connections.

When Not to Use CacheMetadata

 

 

  • When you are working with volatile metadata: Metadata for a table is only retrieved the first time the connection to the table is made. To pick up new, changed, or deleted columns, you would need to delete and rebuild the metadata cache. Therefore, it is best to rely on the in-memory caching for cases where metdata will change often.
  • When you are caching to a database: CacheMetadata can only be used with CacheLocation. If you are caching to another database with the CacheDriver and CacheConnection properties, use AutoCache to cache implicitly. Or, use CACHE Statements to cache explicitly.

 

 

Cache Query Result

Data Type

bool

Default Value

false

Remarks

When CacheQueryResult and AutoCache are set, the rows returned from a SELECT query are cached in the cache database. The driver handles caching in a streaming fashion with each row being processed into the cache database from the original result set as you read the row from the returned ResultSet object. This ensures that the live data is not queried twice. Note that any rows you do not read from the returned ResultSet will not be updated in the cache.

 

Connect On Open

Data Type

bool

Default Value

false

Remarks

When set to 'true', a connection will be made to Elasticsearch when the connection is opened. This property enables the 'Test Connection' feature available in various database tools.

This feature acts as a NOOP command as it is used to verify a connection can be made to Elasticsearch and nothing from this initial connection is maintained.

Setting this property to 'false' may provide performance improvements (depending upon the number of times a connection is opened).

 

Firewall Password

Data Type

string

Default Value

""

Remarks

This property is passed to the proxy specified by FirewallServer and FirewallPort, following the authentication method specified by FirewallType.

 

Firewall Port

Data Type

string

Default Value

""

Remarks

This specifies the TCP port for a proxy allowing traversal of a firewall. Use FirewallServer to specify the name or IP address. Specify the protocol with FirewallType.

 

Firewall Server

Data Type

string

Default Value

""

Remarks

This property specifies the IP address, DNS name, or host name of a proxy allowing traversal of a firewall. The protocol is specified by FirewallType: Use FirewallServer with this property to connect through SOCKS or do tunneling. Use ProxyServer to connect to an HTTP proxy.

Note that the driver uses the system proxy by default. To use a different proxy, set ProxyAutoDetect to false.

 

Firewall Type

Data Type

string

Default Value

"NONE"

Remarks

This property specifies the protocol that the driver will use to tunnel traffic through the FirewallServer proxy. Note that by default the driver connects to the system proxy; to disable this behavior and connect to one of the following proxy types, set ProxyAutoDetect to false.

 

   
Type Default Port Description
TUNNEL 80 When this is set, the driver opens a connection to Elasticsearch and traffic flows back and forth through the proxy.
SOCKS4 1080 When this is set, the driver sends data through the SOCKS 4 proxy specified by FirewallServer and FirewallPort and passes the FirewallUser value to the proxy, which determines if the connection request should be granted.
SOCKS5 1080 When this is set, the driver sends data through the SOCKS 5 proxy specified by FirewallServer and FirewallPort. If your proxy requires authentication, set FirewallUser and FirewallPassword to credentials the proxy recognizes.

 

To connect to HTTP proxies, use ProxyServer and ProxyPort. To authenticate to HTTP proxies, use ProxyAuthScheme, ProxyUser, and ProxyPassword.

 

 

Firewall User

Data Type

string

Default Value

""

Remarks

The FirewallUser and FirewallPassword properties are used to authenticate against the proxy specified in FirewallServer and FirewallPort, following the authentication method specified in FirewallType.

 

Flatten Arrays

Data Type

string

Default Value

""

Remarks

By default, nested arrays are returned as strings of JSON. The FlattenArrays property can be used to flatten the elements of nested arrays into columns of their own. This is only recommended for arrays that are expected to be short.

Set FlattenArrays to the number of elements you want to return from nested arrays. The specified elements are returned as columns. The zero-based index is concatenated to the column name. Other elements are ignored.

For example, you can return an arbitrary number of elements from an array of strings:

"employees": [
  {
    "name": "John Smith",
    "age": 34
  },
  {
    "name": "Peter Brown",
    "age": 26
  },
  {
    "name": "Paul Jacobs",
    "age": 30
  }
]
When FlattenArrays is set to 2, the preceding array is flattened into the following table:

 

   
Column Name Column Value
employees.0.name John Smith
employees.0.age 34
employees.1.name Peter Brown
employees.1.age 26

 

See JSON Functions to use JSON paths to work with unbounded arrays.

 

Flatten Objects

Data Type

bool

Default Value

true

Remarks

Set FlattenObjects to true to flatten object properties into columns of their own. Otherwise, objects nested in arrays are returned as strings of JSON. The property name is concatenated onto the object name with a period to generate the column name.

For example, you can flatten the nested objects below at connection time:

"manager": {
  "name": "Alice White",
  "age": 30
}
When FlattenObjects is set to true, the preceding object is flattened into the following table:

 

   
Column Name Column Value
manager.name Alice White
manager.age 30

 

 

Generate Schema Files

Data Type

string

Default Value

"Never"

Remarks

GenerateSchemaFiles enables you to persist a relational view of Elasticsearch types (tables) or queries; this property outputs schemas to .rsd files in the path specified by Location.

See the following sections for ways to generate schema files or for alternatives. Schema files are easy to edit, but they are static: If you want to regenerate a file, you will first need to delete it.

Available settings are the following:

  • Never: A schema file will never be generated.
  • OnUse: A schema file will be generated the first time a table is referenced, provided the schema file for the table does not already exist.
  • OnStart: A schema file will be generated at connection time for any tables that do not currently have a schema file.
Generate Schemas with SQL

 

By setting GenerateSchemaFiles to OnUse, you can create views on queries you execute. For example, you could specify the XPath to a column value in your SELECT query with an SQL function -- see JSON Functions for examples. See Query Mapping for more information on how to write SQL queries to Elasticsearch.

If you want to write a new query for the view, you will need to first delete the old schema from the Location folder.

Generate Schemas on Connection

 

Another way to use this property is to obtain schemas for every table in your database when you connect. To do so, set GenerateSchemaFiles to OnStart and connect.

See Automatic Schema Discovery to use connection properties to fine-tune the tables rendered.

Editing Schemas

 

Schema files have a simple format that makes them easy to modify. See Custom Schema Definitions for an end-to-end guide.

Alternatives to Static Schemas

 

If your data structures are volatile, consider setting GenerateSchemaFiles to Never and using dynamic schemas. See Automatic Schema Discovery for more information about dynamic schemas.

 

Location

Data Type

string

Default Value

""

Remarks

The path to a directory which contains the schema files for the driver (.rsd files for tables and views, .rsb files for stored procedures). The Location property is only needed if you would like to customize definitions (e.g., change a column name, ignore a column, etc.) or extend the data model with new tables, views, or stored procedures.

The schema files are deployed alongside the driver assemblies. You must also ensure that Location points to the folder that contains the schema files. The folder location can be a relative path from the location of the executable.

 

Logfile

Data Type

string

Default Value

""

Remarks

For more control over what is written to the log file, take a look at Verbosity.

 

Max Log File Size

Data Type

string

Default Value

""

Remarks

A string specifying the maximum size in bytes for a log file (ex: 10MB). When the limit is hit, a new log is created in the same folder with the date and time appended to the end. There is no limit by default. Values lower than 100kB will use 100kB as the value instead.

 

Max Results

Data Type

string

Default Value

"10000"

Remarks

This property corresponds to the Elasticsearch index.max_result_window index setting. Thus the default value is 10000, which is Elasticsearch's default limit.

This value is not applicable when using the Scroll API. Set ScrollDuration to use this API.

When a LIMIT is specified in a query, the LIMIT will be taken into account provided it is less than MaxResults. Otherwise the number of results returned will be limited to the MaxResults value.

If you receive an error stating that the result window is too large, this is caused by the MaxResults value being greater than the Elasticsearch index.max_result_window index setting. You can either change the MaxResults value to match the index.max_result_window index setting or use the Scroll API by setting ScrollDuration.

 

Offline

Data Type

bool

Default Value

false

Remarks

When Offline is set to TRUE, all queries execute against the cache as opposed to the live data source. In this mode, certain queries like INSERT, UPDATE, DELETE, and CACHE are not allowed.

 

Other

Data Type

string

Default Value

""

Remarks

The Other property is a semicolon-separated list of name-value pairs used in connection parameters specific to a data source.

Caching Configuration

 

   
CachePartial=True Caches only a subset of columns, which you can specify in your query.
QueryPassthrough=True Passes the specified query to the cache database instead of using the SQL parser of the driver.

 

Integration and Formatting

 

   
DefaultColumnSize Sets the default length of string fields when the data source does not provide column length in the metadata. The default value is 2000.
ConvertDateTimeToGMT Whether to convert date-time values to GMT, instead of the local time of the machine.
RecordToFile=filename Records the underlying socket data transfer to the specified file.

 

 

Page Size

Data Type

string

Default Value

"10000"

Remarks

The PageSize can control the number of results received per request from Elasticsearch on a given query.

The default value is 10000, which is Elasticsearch's default limit (based on the Elasticsearch index.max_result_window index setting).

 

Password

Data Type

string

Default Value

""

Remarks

 

The password used to authenticate to Elasticsearch.

 

 

Pool Idle Timeout

Data Type

string

Default Value

""

Remarks

The allowed idle time from when the connection is free to when the connection is released and returned to the pool. The default is 60 seconds.

 

Pool Max Size

Data Type

string

Default Value

"100"

Remarks

The maximum connections in the pool. The default is 100. To disable this property, set the property value to 0 or less.

 

Pool Wait Time

Data Type

string

Default Value

""

Remarks

The max seconds to wait for a connection to become available. If a new connection request is waiting for an available connection and exceeds this time, an error is thrown. By default, new requests wait forever for an available connection.

 

Port

Data Type

string

Default Value

"9200"

Remarks

The port the Elasticsearch REST server is bound to.

 

 

Proxy Auth Scheme

Data Type

string

Default Value

"BASIC"

Remarks

This value specifies the authentication type to use to authenticate to the HTTP proxy specified by ProxyServer and ProxyPort.

Note that the driver will use the system proxy settings by default, without further configuration needed; if you want to connect to another proxy, you will need to set ProxyAutoDetect to false, in addition to ProxyServer and ProxyPort. To authenticate, set ProxyAuthScheme and set ProxyUser and ProxyPassword, if needed.

The authentication type can be one of the following:

  • BASIC: The driver performs HTTP BASIC authentication.
  • DIGEST: The driver performs HTTP DIGEST authentication.
  • NEGOTIATE: The driver retrieves an NTLM or Kerberos token based on the applicable protocol for authentication.
  • PROPRIETARY: The driver does not generate an NTLM or Kerberos token. You must supply this token in the Authorization header of the HTTP request.
If you need to use another authentication type, such as SOCKS 5 authentication, see FirewallType.

 

 

Proxy Auto Detect

Data Type

bool

Default Value

true

Remarks

By default, the driver uses the system HTTP proxy. Set this to false if you want to connect to another proxy.

To connect to an HTTP proxy, see ProxyServer.

For other proxies, such as SOCKS or tunneling, see FirewallType.

 

Proxy Exceptions

Data Type

string

Default Value

""

Remarks

The ProxyServer will be used for all addresses, except for addresses defined in this property. Use semicolons to separate entries.

Note that the driver will use the system proxy settings by default, without further configuration needed; if you want to explicitly configure proxy exceptions for this connection, you will need to set ProxyAutoDetect to false, and configure ProxyServer and ProxyPort. To authenticate, set ProxyAuthScheme and set ProxyUser and ProxyPassword, if needed.

 

Proxy Password

Data Type

string

Default Value

""

Remarks

This property is used to authenticate to an HTTP proxy server that supports NTLM (Windows), Kerberos, or HTTP authentication. To specify the HTTP proxy, you can set ProxyServer and ProxyPort. To specify the authentication type, set ProxyAuthScheme.

If you are using HTTP authentication, additionally set ProxyUser and ProxyPassword to HTTP proxy.

If you are using NTLM authentication, set ProxyUser and ProxyPassword to your Windows password. You may also need these to complete Kerberos authentication.

For SOCKS 5 authentication or tunneling, see FirewallType.

By default, the driver uses the system proxy. If you want to connect to another proxy, set ProxyAutoDetect to false.

 

Proxy Port

Data Type

string

Default Value

"80"

Remarks

The port the HTTP proxy is running on that you want to redirect HTTP traffic through. Specify the HTTP proxy in ProxyServer. For other proxy types, see FirewallType.

 

Proxy Server

Data Type

string

Default Value

""

Remarks

The hostname or IP address of a proxy to route HTTP traffic through. The driver can use the HTTP, Windows (NTLM), or Kerberos authentication types to authenticate to an HTTP proxy.

If you need to connect through a SOCKS proxy or tunnel the connection, see FirewallType.

By default, the driver uses the system proxy. If you need to use another proxy, set ProxyAutoDetect to false.

 

Proxy SSL Type

Data Type

string

Default Value

"AUTO"

Remarks

This property determines when to use SSL for the connection to an HTTP proxy specified by ProxyServer. This value can be AUTO, ALWAYS, NEVER, or TUNNEL. The applicable values are the following:

 

   
AUTO Default setting. If the URL is an HTTPS URL, the driver will use the TUNNEL option. If the URL is an HTTP URL, the component will use the NEVER option.
ALWAYS The connection is always SSL enabled.
NEVER The connection is not SSL enabled.
TUNNEL The connection is through a tunneling proxy: The proxy server opens a connection to the remote host and traffic flows back and forth through the proxy.

 

 

Proxy User

Data Type

string

Default Value

""

Remarks

The ProxyUser and ProxyPassword options are used to connect and authenticate against the HTTP proxy specified in ProxyServer.

You can select one of the available authentication types in ProxyAuthScheme. If you are using HTTP authentication, set this to the username of a user recognized by the HTTP proxy. If you are using Windows or Kerberos authentication, set this property to a username in one of the following formats:

user@domain
domain\user

 

 

Pseudo Columns

Data Type

string

Default Value

""

Remarks

This setting is particularly helpful in Entity Framework, which does not allow you to set a value for a pseudo column unless it is a table column. The value of this connection setting is of the format "Table1=Column1, Table1=Column2, Table2=Column3". You can use the "*" character to include all tables and all columns; i.e., "*=*".

 

Query Passthrough

Data Type

bool

Default Value

false

Remarks

Setting this property to True enables the driver to pass an Elasticsearch query as-is to Elasticsearch. The supported query syntax is JSON using the query passthrough syntax described below.

The JSON Passthrough Query Syntax supports the following elements:

 

   
Element Name Function
index The Elasticsearch index (or schema) to query. This is a JSON element that takes a string value.
type The Elasticsearch type (or table) to query within index. This is a JSON element that takes a string value.
docid The Id of the document to query within index.type. This is a JSON element that takes a string value.
apiendpoint The Elasticsearch API Endpoint to query. Default value is '_search'. This is a JSON element that takes a string value.
requestdata The raw Elasticsearch Search DSL that will be sent to Elasticsearch as is. The value is a JSON object that maps directly to the format required by Elasticsearch.

 

The index, type, docid, and apiendpoint are used to generate the URL where the requestdata will be sent. The URL is generated using the following format: [Server]:[Port]/[index]/[type]/[docid]/[apiendpoint]. If any of the JSON passthrough elements are not specified, they will not be added to the URL.

Below is an example of a passthrough query. This example will retrieve the first 10 documents from megacorp.employee that contain a last_name of 'smith'. The results will be ordered by first_name in descending order.

{ 
  "index": "megacorp", 
  "type": "employee", 
  "requestdata": 
  {
    "from": 0,
    "size": 10,
    "query": {"bool":{"must":{"term":{"last_name":"smith"}}}},
    "sort": {"first_name":{"order":"desc"}}
  }
}

 

When using QueryPassthrough queries, the metadata is determined by the data returned in the response. RowScanDepth identifies the depth of the records that will be scanned to determine the metadata (columns and types). Since the metadata is based on the response data, passthrough queries may display different metadata than a similar query performed using the SQL syntax (where the metadata is retrieved directly from Elasticsearch).

 

Readonly

Data Type

bool

Default Value

false

Remarks

If this property is set to true, the driver will allow only SELECT queries. INSERT, UPDATE, DELETE, and stored procedure queries will cause an error to be thrown.

 

Row Scan Depth

Data Type

string

Default Value

"100"

Remarks

This property is used when generating table metadata and specifically is used to identify arrays within the data. Elasticsearch allows any field to be an array and does not identify which fields are arrays in the mapping data. Thus RowScanDepth rows will be queried and scanned to identify if any of the fields contain arrays.

When QueryPassthrough is set to True, the columns in a table must be determined by scanning the data returned in the request. This value determines the maximum number of rows that will be scanned to determine the table metadata. The default value is 100.

Setting a high value may decrease performance. Setting a low value may prevent the data type from being determined properly, especially when there is null data.

 

RTK

Data Type

string

Default Value

""

Remarks

The RTK property may be used to license a build. Please see the included licensing file to see how to set this property. The runtime key is only available if you purchased an OEM license.

 

Scroll Duration

Data Type

string

Default Value

"1m"

Remarks

When a nonzero value is specified, the Scroll API will be used.

The time unit specified will be sent in each request made to Elasticsearch to specify how long the server should keep the search context alive. The value specified only needs to be long enough to process the previous batch of results (not to process all the data). This is because the ScrollDuration value will be sent in each request, which will extend the context time.

Once all the results have been retrieved, the search context will be cleared.

The format for this value is: [integer][time unit]. For example: 1m = 1 minute.

Setting this property to '0' will cause the default Search API to be used. In such a case, the maximum number of results that can be returned are equal to MaxResults.

Supported Time Units:

 

   
Value Description
y Year
M Month
w Week
d Day
h Hour
m Minute
s Second
ms Milli-second

 

 

Server

Data Type

string

Default Value

""

Remarks

The host name or IP address of the Elasticsearch REST server.

To use SSL, prefix the host name or IP address with 'https://' and set SSL connection properties such as SSLServerCert.

 

SSL Client Cert

Data Type

string

Default Value

""

Remarks

The name of the certificate store for the client certificate.

The SSLClientCertType field specifies the type of the certificate store specified by SSLClientCert. If the store is password protected, specify the password in SSLClientCertPassword.

SSLClientCert is used in conjunction with the SSLClientCertSubject field in order to specify client certificates. If SSLClientCert has a value, and SSLClientCertSubject is set, a search for a certificate is initiated. Please refer to the SSLClientCertSubject field for details.

Designations of certificate stores are platform-dependent.

The following are designations of the most common User and Machine certificate stores in Windows:

 

 

   
MY A certificate store holding personal certificates with their associated private keys.
CA Certifying authority certificates.
ROOT Root certificates.
SPC Software publisher certificates.

 

In Java, the certificate store normally is a file containing certificates and optional private keys.

When the certificate store type is PFXFile, this property must be set to the name of the file. When the type is PFXBlob, the property must be set to the binary contents of a PFX file (i.e. PKCS12 certificate store).

 

SSL Client Cert Password

Data Type

string

Default Value

""

Remarks

If the certificate store is of a type that requires a password, this property is used to specify that password in order to open the certificate store.

 

SSL Client Cert Subject

Data Type

string

Default Value

"*"

Remarks

When loading a certificate the subject is used to locate the certificate in the store.

If an exact match is not found, the store is searched for subjects containing the value of the property.

If a match is still not found, the property is set to an empty string, and no certificate is selected.

The special value "*" picks the first certificate in the certificate store.

The certificate subject is a comma separated list of distinguished name fields and values. For instance "CN=www.server.com, OU=test, C=US, E=support@cdata.com". Common fields and their meanings are displayed below.

 

   
Field Meaning
CN Common Name. This is commonly a host name like www.server.com.
O Organization
OU Organizational Unit
L Locality
S State
C Country
E Email Address

 

If a field value contains a comma it must be quoted.

 

SSL Client Cert Type

Data Type

string

Default Value

""

Remarks

This property can take one of the following values:

 

   
USER - default For Windows, this specifies that the certificate store is a certificate store owned by the current user. Note: This store type is not available in Java.
MACHINE For Windows, this specifies that the certificate store is a machine store. Note: this store type is not available in Java.
PFXFILE The certificate store is the name of a PFX (PKCS12) file containing certificates.
PFXBLOB The certificate store is a string (base-64-encoded) representing a certificate store in PFX (PKCS12) format.
JKSFILE The certificate store is the name of a Java key store (JKS) file containing certificates. Note: this store type is only available in Java.
JKSBLOB The certificate store is a string (base-64-encoded) representing a certificate store in Java key store (JKS) format. Note: this store type is only available in Java.
PEMKEY_FILE The certificate store is the name of a PEM-encoded file that contains a private key and an optional certificate.
PEMKEY_BLOB The certificate store is a string (base64-encoded) that contains a private key and an optional certificate.
PUBLIC_KEY_FILE The certificate store is the name of a file that contains a PEM- or DER-encoded public key certificate.
PUBLIC_KEY_BLOB The certificate store is a string (base-64-encoded) that contains a PEM- or DER-encoded public key certificate.
SSHPUBLIC_KEY_FILE The certificate store is the name of a file that contains an SSH-style public key.
SSHPUBLIC_KEY_BLOB The certificate store is a string (base-64-encoded) that contains an SSH-style public key.
P7BFILE The certificate store is the name of a PKCS7 file containing certificates.
PPKFILE The certificate store is the name of a file that contains a PPK (PuTTY Private Key).
XMLFILE The certificate store is the name of a file that contains a certificate in XML format.
XMLBLOB The certificate store is a string that contains a certificate in XML format.

 

 

SSL Server Cert

Data Type

string

Default Value

""

Remarks

If using a TLS/SSL connection, this property can be used to specify the TLS/SSL certificate to be accepted from the server. Any other certificate that is not trusted by the machine will be rejected.

This property can take the forms:

 

   
Description Example
A full PEM Certificate (example shortened for brevity) -----BEGIN CERTIFICATE----- MIIChTCCAe4CAQAwDQYJKoZIhv......Qw== -----END CERTIFICATE-----
A path to a local file containing the certificate C:\cert.cer
The public key (example shortened for brevity) -----BEGIN RSA PUBLIC KEY----- MIGfMA0GCSq......AQAB -----END RSA PUBLIC KEY-----
The MD5 Thumbprint (hex values can also be either space or colon separated) ecadbdda5a1529c58a1e9e09828d70e4
The SHA1 Thumbprint (hex values can also be either space or colon separated) 34a929226ae0819f2ec14b4a3d904f801cbb150d

 

If not specified, any certificate trusted by the machine will be accepted. Use '*' to signify to accept all certificates (not recommended for security concerns).

 

Support Enhanced SQL

Data Type

bool

Default Value

true

Remarks

When SupportEnhancedSQL is set to true, the driver offloads as much of the SELECT statement processing as possible to Elasticsearch and then processes the rest of the query in memory. In this way the driver can execute unsupported predicates, joins, and aggregation.

When SupportEnhancedSQL is set to false, the driver limits SQL execution to what is supported by the Elasticsearch API.

Execution of Predicates

 

The driver determines which of the clauses are supported by the data source and then pushes them to the source to get the smallest superset of rows that would satisfy the query. It then filters the rest of the rows locally. The filter operation is streamed, which enables the driver to filter effectively for even very large datasets.

Execution of Joins

 

The driver uses various techniques to join in memory. The driver trades off memory utilization against the requirement of reading the same table more than once.

Execution of Aggregates

 

The driver retrieves all rows necessary to process the aggregation in memory.

 

Tables

Data Type

string

Default Value

""

Remarks

Listing the tables from some databases can be expensive. Providing a list of tables in the connection string improves the performance of the driver.

This property can also be used as an alternative to automatically listing views if you already know which ones you want to work with and there would otherwise be too many to work with.

Specify the tables you want in a comma-separated list. For example: Tables=TableA,TableB,TableC

 

Timeout

Data Type

string

Default Value

"60"

Remarks

If the Timeout property is set to 0, operations do not time out: They run until they complete successfully or encounter an error condition.

If Timeout expires and the operation is not yet complete, the driver throws an exception.

 

Use Connection Pooling

Data Type

bool

Default Value

false

Remarks

Enables connection pooling. The default is false. See Connection Pooling for information on using connection pools.

 

User

Data Type

string

Default Value

""

Remarks

 

The user who is authenticating to Elasticsearch.

 

Verbosity

Data Type

string

Default Value

"1"

Remarks

The verbosity level determines the amount of detail that the driver reports to the Logfile. Verbosity levels from 1 to 5 are supported. These are described below:

 

   
1 Setting Verbosity to 1 will log the query, the number of rows returned by it, the start of execution and the time taken, and any errors.
2 Setting Verbosity to 2 will log everything included in Verbosity 1, cache queries, and additional information about the request, if applicable, such as HTTP headers.
3 Setting Verbosity to 3 will additionally log the body of the request and the response.
4 Setting Verbosity to 4 will additionally log transport-level communication with the data source. This includes SSL negotiation.
5 Setting Verbosity to 5 will additionally log communication with the data source and additional details that may be helpful in troubleshooting problems. This includes interface commands.

The Verbosity should not be set to greater than 1 for normal operation. Substantial amounts of data can be logged at higher verbosities, which can delay execution times.

 

Views

Data Type

string

Default Value

""

Remarks

Listing the views from some databases can be expensive. Providing a list of views in the connection string improves the performance of the driver.

This property can also be used as an alternative to automatically listing views if you already know which ones you want to work with and there would otherwise be too many to work with.

Specify the views you want in a comma-separated list. For example: For example: Views=ViewsA,ViewsB,ViewsC