COPY VWLOAD
Valid in: SQL, ESQL, OpenAPI
The COPY...VWLOAD statement copies the contents of a file to a table using the VWLOAD operator. This operation is similar to using vwload -c on the command line, except that the load is done from within a multi-statement transaction instead of in a separate session.
Note: COPY VWLOAD has the following limitations at this time: The WITH options ATTRIBUTES and DATEFORMAT do not work. If you specify an invalid or mistyped parameter, it is silently ignored and the load executes (to the extent possible as if that parameter was not there) instead of returning an error.
This statement has the following format:
COPY tablename() VWLOAD FROM 'datafile', ... [WITH option {,option}]
tablename()
Specifies the name of the table to be loaded. The column list is empty and not supported.
'datafile'
Specifies the names of the files, using full or relative paths, that contain the data being loaded. File names are specified as a comma-separated list from one to many. An entry can be a file name, a file name with an asterisk as a wildcard, or a directory. If you specify a directory, all files in the directory are loaded. Valid use of wildcards in file names is as follows: *, abc*, *abc, abc*def, *abc*.
WITH option {,option}
Specifies optional WITH clause options:
ATTRIBUTES='col1, col2, col3,...'
Specifies list of columns to load. An empty col name indicates an input field that is to be ignored.
Default: All columns are loaded if no attributes argument is specified.
AUTO_DETECT_COMPRESSION
Detects GZ and ZIP files. Compressed files are automatically detected by the file contents, not by the file suffix. If you are loading from a directory or using a file name wildcard, you can mix regular text files, GZ, and ZIP.
AWS_ACCESS_KEY='my_access_key'
Specifies the access key ID to access your S3 bucket on Amazon Web Services.
AWS_SECRET_KEY='my_secret_key'
Specifies the secret access key used to access to your S3 bucket on Amazon Web Services.
AZURE_CLIENT_ENDPOINT='https://login.microsoftonline.com/tenant_id/oauth2/token'
Specifies the Directory (tenant) ID used to access your Azure Storage account.
AZURE_CLIENT_ID = 'client_id'
Specifies the Application (client) ID used to access your Azure Storage account.
AZURE_CLIENT_SECRET = 'client_secret'
Specifies the Client Secret (password) used to access your Azure Storage account.
CHARSET='charset'
Default: no conversion
DATEFORMAT='col1=format1,col2=format2,...'
Sets date format for the 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 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. Default: US
Examples:
WITH DATEFORMAT='col1=+'%d-%b-%y'
WITH DATEFORMAT='Col1=US,Col2=+%M %Y %d'
ERRCOUNT=n
Terminates after the first n errors in all input files. Default: 0 (do not terminate).
ESCAPE='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
ESCAPES
Interprets data escape sequences
FDELIM='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: "|"
HEADER
Skips header line in files.
IGNFIRST
Ignores the first field.
IGNLAST
Ignores the last field.
INSERTMODE=
Specifies the mode to use for inserts and merges. Valid modes are:
ROW
Inserts through the PDT (allows concurrent inserts)
BULK
Appends directly to disk (does not allow concurrent inserts)
LOG='dir'
Logs rejected rows and corresponding errors to the specified file. The file is created by the operation.
NONCHAR_LEADING_SPACES_NULL
When –nullvalue is used, data may contain spaces in front of the null identifiers. This option applies to non-character columns only. For example, if --nullvalue NADA is specified, –nonchar_leading_spaces_null will interpret a DATE column containing “NADA” or “ NADA” as NULL.
NOTNULL_EMPTY
Keeps empty strings. Does not consider the input value NULL if it is empty (that is, contains two consecutive field delimiters). For VARCHAR, the value becomes an empty string; for CHAR the value becomes blanks. This option applies only to CHAR, NCHAR, VARCHAR, and NVARCHAR columns that are NOT NULL.
NULLVALUE='nullvalue'
Defines the string that identifies NULL values.
Default: ' '
QUOTE='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].
To specify a control character, use an escape sequence.
Default: none
RDELIM='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=
Turns “roll back on error” on or off.
ON
(Default) Rolls back on error.
OFF
Does not roll back the load transaction when errors were encountered, causing partial data to be loaded.
STRICTNULLS
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'
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 (see
vwload Escape Sequences).
TEXTMODE
Opens input files in text mode and does not perform newline conversion. On Linux, this may gain a 5 to 10 percent performance improvement. On Windows, there is no known advantage to using this option. (By default, vwload opens files in binary mode and performs automatic newline conversion, transparently handling text formats of various operating systems.)
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.
WORK_DIR
Specifies a directory that will be used for relative paths in filenames. Default is /tmp, so specifying non-absolute paths without a WORK_DIR tells Vector to look for the files in /tmp.
COPY VWLOAD Examples
1. Bulk load the data from multiple files into the mytable table. Columns in the data file are delimited with a vertical bar, records are delimited by a new line, and null values are identified as NULL:
COPY mytable() VWLOAD FROM 'hdfs://namenode:8020/path/to/data/mytable_1.txt', 'hdfs://namenode:8020/path/to/data/mytable_2.txt' WITH INSERTMODE=BULK, FDELIM='|', RDELIM='\n', NULLVALUE='NULL', WORK_DIR = '/home/users/temp'
2. Load data from multiple files residing in Azure Data Lake Storage into the lineitem table.
COPY lineitem() VWLOAD FROM
'abfs://loadtest@avalanchetest.dfs.core.windows.net/firstfolder/lineitem10.tbl',
'abfs://loadtest@avalanchetest.dfs.core.windows.net/firstfolder/lineitem10_2.tbl',
'abfs://loadtest@avalanchetest.dfs.core.windows.net/firstfolder/lineitem10_3.tbl',
'abfs://loadtest@avalanchetest.dfs.core.windows.net/firstfolder/lineitem10_4.tbl',
'abfs://loadtest@avalanchetest.dfs.core.windows.net/firstfolder/lineitem10_5.tbl',
'abfs://loadtest@avalanchetest.dfs.core.windows.net/firstfolder/lineitem10_6.tbl'
WITH
AZURE_CLIENT_ENDPOINT = 'https://login.microsoftonline.com/TENANT_ID/oauth2/token',
AZURE_CLIENT_ID = 'CLIENT_ID',
AZURE_CLIENT_SECRET = 'CLIENT_SECRET'
vwload Escape Sequences
To specify control characters in the vwload command, you must use an escape sequence. An escape sequence is initiated by a \ character. Valid escape sequences are:
Note: Certain special characters, such as \, ", ‘, and |, must be protected from interpretation by the command shell by using the appropriate quoting and escaping mechanisms provided by the shell. This does not apply to Actian Director, which automatically takes care of such formatting.
vwload Date Format Settings
The ‑‑dateformat format | attr=format option on the vwload command sets the date format for the attribute (column).
Valid settings for format as follows:
For a date that is missing the century on input, year is determined by the setting on the II_DATE_CENTURY_BOUNDARY environment variable.
In three-character month formats, for example, dd-mmm-yy, specify three-letter abbreviations for the month (for example, mar, apr, may).
To specify the current system date and time, use the constant, NOW.
vwload Supported Character Sets
Character sets supported on the vwload --charset option are as follows: