vwload Command--Load Data into a Table
The vwload command loads data into a Vector table.
By default, errors do not stop the loading process; however, when an error is encountered, the load is rolled back. Use command options to modify the default behavior.
This command has the following format:
vwload --table tablename [vnode::]dbname [options] datafile ...
--table tablename, -t tablename
Specifies the name of the table that data is to be loaded into.
[vnode::]dbname
Specifies the ID of the remote node (if connecting to a remote server) and name of the database.
datafile
Specifies the name of the file that contains the data being loaded. Multiple files can be specified.
options
Specify options, as follows:
-‑attributes attr1,attr2... , -a attr1,attr2...,
Specifies list of attributes (columns) to load. An empty attr name indicates an input field that is to be ignored.
Default: All attributes are loaded if no ‑‑attributes argument is specified.
‑‑cluster, -c
Speeds up loading by parallelizing some of the processing steps.
--charset charset, -C charset
Default: no conversion
--dateformat format | attr=format,..., -d format | attr=format,...
Sets date or timestamp format for the attribute (column). When no attribute is indicated, the value applies to all attributes that are not otherwise set.
Alternatively, a custom format string can be specified by starting the format with a '+' sign followed by the format string. The format string can consist of any of the format specifier characters used on the DATE_FORMAT function, described in the Vector SQL Language Guide.
To be able to use any character in the format string (including for example, "," and "="), you must quote the format string in the same way that you would quote a delimited identifier on the command line (for example: 'ColX="+%M,%Y,%d",ColY=US'). For more information on delimited identifiers, see Regular and Delimited Identifiers in the Vector SQL Language Guide.
Default: US
Examples:
vwload -d col1=+'%d-%b-%y' -t table1 mydb date.in
vwload -d 'Col1=US,Col2=+%M %Y %d' -t table1 mydb2 loadfile.txt
--errcount n, -x n
Terminates after n errors.
When used with the ‑‑cluster option, terminates after the first n errors in all input files. For details, see
vwload in Parallel Mode.
Default: 0 (do not terminate)
--escapes, -E
Interprets data escape sequences as generated by MySQL and PostgreSQL. This also allows setting \N as the NULL representation.
Note: The \0, \digits, and \xdigits escape sequences are not supported.
‑‑escape escapechar, -e escapechar
Specifies the escape character to use. This allows escaping of single characters to allow a delimiter character to be part of a field (for example: \) or to allow a quote character to be part of a quoted string.
The argument must be a single ASCII character or an empty string. If the argument is an empty string, this functionality is disabled. To specify a control character, use an escape sequence (see
vwload Escape Sequences).
Default: none
--fdelim fielddelim, -f fielddelim
Specifies field delimiter to use. The delimiter must be a single character. To specify a control character, use an escape sequence (see
vwload Escape Sequences).
Default: "|"
--frequency frequency, ‑F
Sets the frequency of verbose progress reports, in number of records. Optionally append one of k K m M g G as magnitude multiplier. For example: 5M means print a report every 5 million records.
--header, -H
Skips header line in files.
--help, -h
Displays syntax information.
--ignfirst, -i
Ignores the first field.
--ignlast, -I
Ignores the last field.
--log file, -l file
Logs rejected rows and corresponding errors to the specified file. The file is created by vwload.
When used with the ‑‑cluster option, specify a directory name instead of a file name. For details, see
vwload in Parallel Mode.
--nullvalue nullvalue, -n nullvalue
Defines the string that identifies NULL values.
Default: ""
--password password, -P password
Specifies the user password.
Note: Specifying the password on the command line is insecure because the command line can be viewed by other users with programs such as ps. Vwload overwrites the password on the command line with zeros during program initialization to reduce the security risk, but a short time still exists where the password is visible to other users. It is more secure to let the program prompt for the password.
Default: Prompts on TTY when needed.
--quote quotechar, -q quotechar
Specifies the quote character(s) to use. This allows the input to contain quoted fields (for example "Doe, John"), which may contain field or record delimiter characters. To include a quote character inside a quoted field, enter it twice in the input--for example: "The ""BIG"" Boss". When using distinct open and close quote characters, enter only the close quote character twice--for example: [The [BIG]] Boss].
The argument must be one or two ASCII characters or an empty string.
If the argument is an empty string, this functionality is disabled. If the argument is two characters, the first character is used as the opening quote character, and the second as the closing quote character. For example, specify "[]" to allow [quoted string].
Default: none
--rdelim recorddelim, -r recorddelim
Specifies record delimiter to use. The delimiter must be a single character. To specify a control character, use an escape sequence (see
vwload Escape Sequences).
Default: "\n"
--rollback on|off, -B on|off
Turns roll back on error on or off. If set to off, the load transaction will not be rolled back when errors were encountered, causing partial data to be loaded.
Default: on
--rowmode, -R
Inserts data through the PDT (in-memory) updates, rather than directly appending the data in bulk to the table's data blocks on disk. This allows concurrent inserts, at the cost of decreased performance at high bulk volume, increased memory consumption. At the time of the load, the whole volume of loaded data will have to fit in memory, and only later it will be propagated to the table's blocks on disk through update propagation.
--skip n, -s n
Specifies the number of records to skip.
Default: 0
--stats, -z
Creates statistics for the table. Builds histograms for all columns of the loaded table.
--strictnulls, -N
Uses strict NULL value checking. This distinguishes between plain and quoted or escaped occurrences of a NULL representation. For example, NULL is a NULL value, whereas "NULL" is a 4-character string value. By default, vwload does not make this distinction. This option allows proper loading of some data generated by MySQL and PostgreSQL.
--substitute substitutechar, -S substitutechar
Substitutes the specified character for any invalid input character during character set conversion. When no substitute character is provided, an invalid input character is considered an error condition. Specifying a substitute character allows records that contain invalid characters to be loaded successfully.
The argument must be a single Unicode character or an empty string. If the argument is an empty string, the functionality is disabled.
To specify a control character or Unicode code point that cannot easily be typed on the keyboard, use an escape sequence.
--textmode, -T
Opens input files in text mode and does not perform newline conversion. On Linux, this may gain a 5 to 10 percent performance improvement.
Note: When using -T on Windows, any ^Z (ASCII SUB) character in the input is interpreted as End-Of-File by the Windows library, and causes vwload not to see any data following the first such character.
--timing, -m
Enables timing information. Timing statistics will be printed at the end. In verbose mode, they will be printed for every progress update.
+user=authuser[,password]
--user username, -u username
Specifies the effective user for the session.
--verbose, -v
Prints progress report.