pgFetch

pgFetch#

pgFetch(connect, second_input, varargin)#

Fetch data and metadata from PostgreSQL using a connection or prepared statement.

Parameters:

  • connect (database.relational.connection) – Open database connection

  • second_input (char | string | database.preparedstatement.SQLPreparedStatement) – SQL query string or prepared statement

  • varargin (any) – Optional arguments

Returns:

Fetched data

Return type:

table | cell | struct | numeric

Returns:

Metadata describing returned data

Return type:

struct

Options (name-value):

  • MaxRows: Maximum number of rows to return (default 0 = unlimited)

  • VariableNamingRule: “preserve” or “modify” (table output only)

  • DataReturnFormat: one of “table” (default) | “cellarray” | “structure” | “numeric”

  • RowFilter: matlab.io.RowFilter to push down to SQL

  • rowlimit_or_opts: Either a row-limit scalar or a SQLImportOptions object

Notes:

When a prepared statement is provided, certain options are mutually exclusive (e.g., RowFilter and import options). See MATLAB Database Toolbox behavior.

DATA = FETCH(CONN,SQLSTRING) imports database data into MATLAB given the connection handle, CONN, and the SQL string, SQLSTRING.

DATA = FETCH(CONN,SQLSTRING,OPTS) imports database data into MATLAB using the specified import options opts.

DATA = FETCH(CONN,SQLSTRING,NAME,VALUE) imports database data into MATLAB with additional options specified by one or more name-value arguments. For e.g., you can specify DataReturnFormat or MaxRows name-value argument.

DATA = FETCH(CONN,PSTMT) imports database data into MATLAB given the connection handle, CONN, and the SQLPreparedStatement, PSTMT.

DATA = FETCH(CONN,PSTMT,NAME,VALUE) imports database data into MATLAB with additional options specified by one or more name-value arguments. For e.g., you can specify DataReturnFormat or MaxRows name-value argument.

[data,metadata] = FETCH(_____) imports database data into MATLAB and metadata information for imported data

conn - database.jdbc.connection object. source - SQL query or SQLPreparedStatement.

opts - import options for sql query defined using databaseImportOptions DataReturnFormat - type of data returned. table (default) | cellarray | structure | numeric MaxRows - Maximum number of rows to return VariableNamingRule - determine use of arbitrary variable names

For example,

data = fetch(conn,’select * from tablename’) will return the data as a table by default.

[data,metadata] = fetch(conn,’select * from tablename’,’DataReturnFormat’,’cellarray’) will return the data as a cell array.

data = fetch(conn,’select * from tablename’,opts) will return the data using import options specified using opts.

See also connection/sqlread, databaseImportOptions