fe_exec_m Module

private function PQexecParams_int32(conn, command, nParams, paramTypes, paramValues) result(res)

Submits a command to the server and waits for the result, with the ability to pass parameters separately from the SQL command text.

PQexecParams is like PQexec but offers additional functionality: parameter values can be specified separately from the command string proper, and query results can be requested in text or binary format.

cf. PostgreSQL Documentation

Example

 block
    character(:), allocatable :: command
    character(8) :: values(2)
    type(c_ptr) :: res

    command = "select $1::bigint + $2::bigint;"
    values(1) = "300"
    values(2) = "500"

    res = PQexecParams(conn, command, size(values), [0, 0], values)
    if (PQresultStatus(res) /= PGRES_TUPLES_OK) then
       print *, PQerrorMessage(conn)
       call PQclear(res)
    end if

    print *, PQgetvalue(res, 0, 0) ! the result "800" is expected.
    call PQclear(res)

cf. PostgreSQL Documentation

Arguments

Return Value type(c_ptr)

private function PQexecParams_int64(conn, command, nParams, paramTypes, paramValues) result(res)

Submits a command to the server and waits for the result, with the ability to pass parameters separately from the SQL command text.

PQexecParams is like PQexec but offers additional functionality: parameter values can be specified separately from the command string proper, and query results can be requested in text or binary format.

cf. PostgreSQL Documentation

Example

 block
    character(:), allocatable :: command
    character(8) :: values(2)
    type(c_ptr) :: res

    command = "select $1::bigint + $2::bigint;"
    values(1) = "300"
    values(2) = "500"

    res = PQexecParams(conn, command, size(values), [0_8, 0_8], values)
    if (PQresultStatus(res) /= PGRES_TUPLES_OK) then
       print *, PQerrorMessage(conn)
       call PQclear(res)
    end if

    print *, PQgetvalue(res, 0, 0) ! the result "800" is expected.
    call PQclear(res)

cf. PostgreSQL Documentation

Arguments

Return Value type(c_ptr)

private function PQprepare_int32(conn, stmtName, query, nParams, paramTypes) result(res)

Submits a request to create a prepared statement with the given parameters, and waits for completion.

PQprepare creates a prepared statement for later execution with PQexecPrepared. This feature allows commands to be executed repeatedly without being parsed and planned each time; see PREPARE for details.

The function create a prepared statement named stmtName from the query string, which must contain a single SQL command. stmtName can be "" to create an unnamed statement, in which case any pre-existing unnamed statement is automatically replaced; otherwise it is an error if the statement name is already defined in the current session. If any parameters are used, they are referred to in the as $1, $2, etc. nParams is the number of parameters for which types are pre-specified in the array paramTypes. paramTypes specifies, by OID, the data types to be assigned to the parameter symbols. If any particuler element in the paramTypes array is zero, the server assigns a data type to the parameter symbol in the same way it would do for an untyped literal string. Also, the query can use parameter symbols with the numbers higher than nParams; data types will be inferred for these symbols as well. (See PQdescribePrepared) for a means to find out what data types were inffered.)

As with [[PQexec]], the result is normally a PGresult object whose contents indicate server-side success or failure. A null result indicates out-of-memory or inability to send to the command at all. Use PQerrorMessage to get more information about such errors.

cf. PostgreSQL Documentation

Arguments

Return Value type(c_ptr)

private function PQprepare_int64(conn, stmtName, query, nParams, paramTypes) result(res)

Submits a request to create a prepared statement with the given parameters, and waits for completion.

PQprepare creates a prepared statement for later execution with PQexecPrepared. This feature allows commands to be executed repeatedly without being parsed and planned each time; see PREPARE for details.

The function create a prepared statement named stmtName from the query string, which must contain a single SQL command. stmtName can be "" to create an unnamed statement, in which case any pre-existing unnamed statement is automatically replaced; otherwise it is an error if the statement name is already defined in the current session. If any parameters are used, they are referred to in the as $1, $2, etc. nParams is the number of parameters for which types are pre-specified in the array paramTypes. paramTypes specifies, by OID, the data types to be assigned to the parameter symbols. If any particuler element in the paramTypes array is zero, the server assigns a data type to the parameter symbol in the same way it would do for an untyped literal string. Also, the query can use parameter symbols with the numbers higher than nParams; data types will be inferred for these symbols as well.

As with PQexec, the result is normally a PGresult object whose contents indicate server-side success or failure. A null result indicates out-of-memory or inability to send to the command at all. Use PQerrorMessage to get more information about such errors.

cf. PostgreSQL Documentation

cf. PostgreSQL Documentation

Arguments

Return Value type(c_ptr)

private function PQsendPrepare_int32(conn, stmtName, query, nParams, paramTypes) result(res)

Sends a request to create a prepared statement with the given parameters, without waiting for completion.

This is an asynchronous version of PQprepare: it returns 1 if it was able to dispatch the request, and 0 if not. After a successfull call, call PQgetResult to determine whether the server successfully created the prepared statement. The function's parameters are handled identically to PQprepare.

cf. PostgreSQL Documentation

Arguments

Return Value integer(kind=int32)

private function PQsendPrepare_int64(conn, stmtName, query, nParams, paramTypes) result(res)

Sends a request to create a prepared statement with the given parameters, without waiting for completion.

This is an asynchronous version of PQprepare: it returns 1 if it was able to dispatch the request, and 0 if not. After a successfull call, call PQgetResult to determine whether the server successfully created the prepared statement. The function's parameters are handled identically to PQprepare.

cf. PostgreSQL Documentation cf. PostgreSQL Documentation

Arguments

Return Value integer(kind=int32)

private function PQsendQueryPrepared_text(conn, stmtName, nParams, paramValues) result(res)

cf. PostgreSQL Documentation

Arguments

Return Value integer(kind=int32)

private function PQsendQueryParams_int32(conn, command, nParams, paramTypes, paramValues) result(res)

Submit a command and separate parameter to the server without waiting for the result(s). This is equivalent to PQsendQuery, except that query parameters can be specified separately form the query string. This function's parameters are handled identically PQexecParams. Like PQexecParams, it allows only one command in the query.

cf. PostgreSQL Documentation

Arguments

Return Value integer(kind=int32)

private function PQsendQueryParams_int64(conn, command, nParams, paramTypes, paramValues) result(res)

Submit a command and separate parameter to the server without waiting for the result(s). This is equivalent to PQsendQuery, except that query parameters can be specified separately form the query string. This function's parameters are handled identically PQexecParams. Like PQexecParams, it allows only one command in the query.

cf. PostgreSQL Documentation

Arguments

Return Value integer(kind=int32)