verticapy.read_csv¶
- verticapy.read_csv(path: str, schema: str | None = None, table_name: str | None = None, sep: str | None = None, header: bool = True, header_names: list | None = None, dtype: dict | None = None, na_rep: str | None = None, quotechar: str = '"', escape: str = '\x17', record_terminator: str | None = '\n', trim: bool = True, omit_empty_keys: bool = False, reject_on_duplicate: bool = False, reject_on_empty_key: bool = False, reject_on_materialized_type_error: bool = False, parse_nrows: int = -1, insert: bool = False, temporary_table: bool = False, temporary_local_table: bool = True, gen_tmp_table_name: bool = True, ingest_local: bool = True, genSQL: bool = False, materialize: bool = True) vDataFrame¶
Ingests a CSV file using flex tables.
Parameters¶
- path: str
Absolute path where the CSV file is located.
- schema: str, optional
Schema where the CSV file will be ingested.
- table_name: str, optional
The final relation/table name. If unspecified, the name is set to the name of the file or parent directory.
- sep: str, optional
Column separator.
- header: bool, optional
If set to
False, the parameterheader_namesis used to name the different columns.- header_names: list, optional
listof the column names.- dtype: dict, optional
dictionaryof the user types. Providing adictionarycan increase ingestion speed and precision; instead of parsing the file to guess the different types, VerticaPy will use the input types.- na_rep: str, optional
Missing values representation.
- quotechar: str, optional
Char that encloses the
strvalues.- escape: str, optional
Separator between each record.
- record_terminator: str, optional
A single-character value used to specify the end of a record.
- trim: bool, optional
boolean, specifies whether to trim white space from header names and key values.- omit_empty_keys: bool, optional
boolean, specifies how the parser handles header keys without values. IfTrue, keys with an empty value in the header row are not loaded.- reject_on_duplicate: bool, optional
boolean, specifies whether to ignore duplicate records (False), or to reject duplicates (True). In either case, the load continues.- reject_on_empty_key: bool, optional
boolean, specifies whether to reject any row containing a key without a value.- reject_on_materialized_type_error: bool, optional
boolean, specifies whether to reject any materialized column value that the parser cannot coerce into a compatible data type.- parse_nrows: int, optional
If this parameter is greater than zero, a new file of
parse_nrowsrows is created and ingested to identify the data types. It is then dropped and the entire file is ingested. The data types identification will be less precise but this parameter can make the process faster if the file is large.- insert: bool, optional
If set to
True, the data is ingested into the specified input relation. Be sure that your file has a header corresponding to the name of the relation columns, otherwise ingestion will fail.- temporary_table: bool, optional
If set to
True, a temporary table will be created.- temporary_local_table: bool, optional
If set to
True, a temporary local table will be created. The parameterschemamust be empty, otherwise this parameter is ignored.- gen_tmp_table_name: bool, optional
Sets the name of the temporary table. This parameter is only used when the parameter
temporary_local_tableis set toTrueand if the parameterstable_nameandschemaare unspecified.- ingest_local: bool, optional
If set to
True, the file is ingested from the local machine.- genSQL: bool, optional
If set to
True, the SQL code for creating the final table is generated but not executed. This is a good way to change the final relation types or to customize the data ingestion.- materialize: bool, optional
If set to
True, the flex table is materialized into a table. Otherwise, it will remain a flex table. Flex tables simplify the data ingestion but have worse performace compared to regular tables.
Returns¶
- vDataFrame
The
vDataFrameof the relation.
Examples¶
In this example, we will first create a CSV file using
vDataFrame.to_csv()and ingest it into Vertica database.We import
verticapy:import verticapy as vp
Hint
By assigning an alias to
verticapy, we mitigate the risk of code collisions with other libraries. This precaution is necessary because verticapy uses commonly known function names like “average” and “median”, which can potentially lead to naming conflicts. The use of an alias ensures that the functions fromverticapyare used as intended without interfering with functions from other libraries.We will use the Titanic dataset.
import verticapy.datasets as vpd data = vpd.load_titanic()
123pclass123survivedAbcAbcsex123age123sibsp123parchAbcticket123fareAbccabinAbcembarkedAbcboat123bodyAbc1 1 0 male 71.0 0 0 PC 17609 49.5042 [null] C [null] 22 2 1 0 male 45.0 0 0 113784 35.5 T S [null] [null] 3 1 0 male [null] 0 0 113798 31.0 [null] S [null] [null] 4 1 0 male 17.0 0 0 113059 47.1 [null] S [null] [null] 5 1 0 male 27.0 1 0 13508 136.7792 C89 C [null] [null] 6 1 0 male 37.0 1 1 PC 17756 83.1583 E52 C [null] [null] 7 1 0 male 31.0 1 0 F.C. 12750 52.0 B71 S [null] [null] 8 1 0 male 50.0 1 0 PC 17761 106.425 C86 C [null] 62 9 1 0 female 36.0 0 0 PC 17531 31.6792 A29 C [null] [null] 10 1 0 male 37.0 1 0 113803 53.1 C123 S [null] [null] 11 1 0 male 24.0 0 0 PC 17593 79.2 B86 C [null] [null] 12 1 0 male 45.0 1 0 36973 83.475 C83 S [null] [null] 13 1 0 male 40.0 0 0 112059 0.0 B94 S [null] 110 14 1 0 male 42.0 0 0 113038 42.5 B11 S [null] [null] 15 1 0 male [null] 0 0 17463 51.8625 E46 S [null] [null] 16 1 0 male 42.0 1 0 113789 52.0 [null] S [null] 38 17 1 0 male [null] 0 0 PC 17600 30.6958 [null] C 14 [null] 18 1 0 male 29.0 0 0 113501 30.0 D6 S [null] 126 19 1 0 male 46.0 0 0 13050 75.2417 C6 C [null] 292 20 1 0 male 54.0 0 0 17463 51.8625 E46 S [null] 175 21 1 0 male 47.0 0 0 113796 42.4 [null] S [null] [null] 22 1 0 male 58.0 0 2 35273 113.275 D48 C [null] 122 23 1 0 male 45.5 0 0 113043 28.5 C124 S [null] 166 24 1 0 male 29.0 1 0 113776 66.6 C2 S [null] [null] 25 1 0 male 47.0 0 0 110465 52.0 C110 S [null] 207 26 1 0 male 38.0 0 0 19972 0.0 [null] S [null] [null] 27 1 0 male 22.0 0 0 PC 17760 135.6333 [null] C [null] 232 28 1 0 male 31.0 0 0 PC 17590 50.4958 A24 S [null] [null] 29 1 0 male 50.0 1 0 13507 55.9 E44 S [null] [null] 30 1 0 male 56.0 0 0 17764 30.6958 A7 C [null] [null] 31 1 0 male 57.0 1 0 PC 17569 146.5208 B78 C [null] [null] 32 1 0 female 63.0 1 0 PC 17483 221.7792 C55 C57 S [null] [null] 33 1 0 male 61.0 0 0 36963 32.3208 D50 S [null] 46 34 1 0 male 21.0 0 1 35281 77.2875 D26 S [null] 169 35 1 0 male 51.0 0 1 PC 17597 61.3792 [null] C [null] [null] 36 1 1 female 63.0 1 0 13502 77.9583 D7 S 10 [null] 37 1 1 female 32.0 0 0 11813 76.2917 D15 C 8 [null] 38 1 1 female 58.0 0 0 113783 26.55 C103 S 8 [null] 39 1 1 female 44.0 0 0 PC 17610 27.7208 B4 C 6 [null] 40 1 1 female 41.0 0 0 16966 134.5 E40 C 3 [null] 41 1 1 female 53.0 0 0 PC 17606 27.4458 [null] C 6 [null] 42 1 1 male 36.0 0 1 PC 17755 512.3292 B51 B53 B55 C 3 [null] 43 1 1 female 58.0 0 1 PC 17755 512.3292 B51 B53 B55 C 3 [null] 44 1 1 male 11.0 1 2 113760 120.0 B96 B98 S 4 [null] 45 1 1 female 76.0 1 0 19877 78.85 C46 S 6 [null] 46 1 1 female [null] 0 1 113505 55.0 E33 S 6 [null] 47 1 1 female 39.0 1 1 PC 17756 83.1583 E49 C 14 [null] 48 1 1 female 27.0 1 2 F.C. 12750 52.0 B71 S 3 [null] 49 1 1 female [null] 0 0 17421 110.8833 [null] C 4 [null] 50 1 1 female 35.0 0 0 113503 211.5 C130 C 4 [null] 51 1 1 female 22.0 0 1 112378 59.4 [null] C 7 [null] 52 1 1 female 25.0 1 0 11765 55.4417 E50 C 5 [null] 53 1 1 male 48.0 1 0 PC 17572 76.7292 D33 C 3 [null] 54 1 1 female 35.0 1 0 36973 83.475 C83 S D [null] 55 1 1 male 27.0 0 0 PC 17572 76.7292 D49 C 3 [null] 56 1 1 female 24.0 0 0 11767 83.1583 C54 C 7 [null] 57 1 1 female 52.0 1 1 12749 93.5 B69 S 3 [null] 58 1 1 female 44.0 0 1 111361 57.9792 B18 C 4 [null] 59 1 1 female 15.0 0 1 24160 211.3375 B5 S 2 [null] 60 1 1 male 30.0 1 0 13236 57.75 C78 C 11 [null] 61 1 1 female 31.0 1 0 35273 113.275 D36 C 6 [null] 62 1 1 female 39.0 0 0 PC 17758 108.9 C105 C 8 [null] 63 1 1 female 22.0 0 1 113509 61.9792 B36 C 5 [null] 64 1 1 male 52.0 0 0 113786 30.5 C104 S 6 [null] 65 1 1 female 43.0 0 1 24160 211.3375 B3 S 2 [null] 66 1 1 female 33.0 0 0 110152 86.5 B77 S 8 [null] 67 1 1 male 45.0 1 1 16966 134.5 E34 C 3 [null] 68 1 1 female 40.0 1 1 16966 134.5 E34 C 3 [null] 69 1 1 male 48.0 1 0 19996 52.0 C126 S 5 7 [null] 70 1 1 female [null] 0 0 PC 17585 79.2 [null] C D [null] 71 1 1 female 35.0 0 0 PC 17755 512.3292 [null] C 3 [null] 72 1 1 female 60.0 1 0 110813 75.25 D37 C 5 [null] 73 1 1 male 21.0 0 1 PC 17597 61.3792 [null] C A [null] 74 2 0 male 23.0 0 0 C.A. 31030 10.5 [null] S [null] [null] 75 2 0 male 28.0 0 0 244358 26.0 [null] S [null] [null] 76 2 0 male 60.0 1 1 29750 39.0 [null] S [null] [null] 77 2 0 female 44.0 1 0 244252 26.0 [null] S [null] [null] 78 2 0 male 29.0 1 0 2003 26.0 [null] S [null] [null] 79 2 0 male 18.0 0 0 S.O.C. 14879 73.5 [null] S [null] [null] 80 2 0 male 18.0 0 0 S.O.C. 14879 73.5 [null] S [null] [null] 81 2 0 male 54.0 0 0 28403 26.0 [null] S [null] [null] 82 2 0 male 18.0 0 0 236171 13.0 [null] S [null] [null] 83 2 0 male 36.0 0 0 229236 13.0 [null] S [null] 236 84 2 0 male 34.0 1 0 28664 21.0 [null] S [null] [null] 85 2 0 male 21.0 1 0 28133 11.5 [null] S [null] [null] 86 2 0 male 21.0 1 0 28134 11.5 [null] S [null] [null] 87 2 0 male 24.0 0 0 233866 13.0 [null] S [null] 155 88 2 0 male 34.0 0 0 12233 13.0 [null] S [null] [null] 89 2 0 male 30.0 0 0 250653 13.0 [null] S [null] 75 90 2 0 male 44.0 0 0 248746 13.0 [null] S [null] 35 91 2 0 male 49.0 1 2 220845 65.0 [null] S [null] [null] 92 2 0 male 21.0 2 0 S.O.C. 14879 73.5 [null] S [null] [null] 93 2 0 male 21.0 0 0 S.O.C. 14879 73.5 [null] S [null] [null] 94 2 0 female 60.0 1 0 24065 26.0 [null] S [null] [null] 95 2 0 male 24.0 2 0 C.A. 31029 31.5 [null] S [null] [null] 96 2 0 male 22.0 2 0 C.A. 31029 31.5 [null] S [null] [null] 97 2 0 male 35.0 0 0 233734 12.35 [null] Q [null] [null] 98 2 0 male 31.0 0 0 C.A. 18723 10.5 [null] S [null] 165 99 2 0 male 36.0 0 0 SC/Paris 2163 12.875 D C [null] [null] 100 2 0 male [null] 0 0 SC/A.3 2861 15.5792 [null] C [null] [null] Rows: 1-100 | Columns: 14Note
VerticaPy offers a wide range of sample datasets that are ideal for training and testing purposes. You can explore the full list of available datasets in the Datasets, which provides detailed information on each dataset and how to use them effectively. These datasets are invaluable resources for honing your data analysis and machine learning skills within the VerticaPy environment.
Let’s convert the
vDataFrameto a CSV.data[0:20].to_csv( path = "titanic_subset.csv", )
Our CSV file is ready to be ingested in database.
Let’s generate, the SQL needed to create the Table.
from verticapy.core.parsers.csv import read_csv read_csv( path = "titanic_subset.csv", table_name = "titanic_subset", schema = "public", quotechar = '"', sep = ",", na_rep = "", genSQL = True, ) Out[4]: ['CREATE TABLE "public"."titanic_subset"("pclass" Integer, "survived" Integer, "name" Varchar(64), "sex" Varchar(20), "age" Numeric(8,4), "sibsp" Integer, "parch" Integer, "ticket" Varchar(20), "fare" Numeric(11,6), "cabin" Varchar(20), "embarked" Varchar(20), "boat" Integer, "body" Integer, "home.dest" Varchar(64))', 'COPY "public"."titanic_subset"("pclass", "survived", "name", "sex", "age", "sibsp", "parch", "ticket", "fare", "cabin", "embarked", "boat", "body", "home.dest") FROM LOCAL \'titanic_subset.csv\' UNCOMPRESSED DELIMITER \',\' NULL \'\' ENCLOSED BY \'"\' RECORD TERMINATOR E\'\\n\' ESCAPE AS \'\x17\' SKIP 1']
Note
When
genSQLflag is set toTrue, the SQL code for creating the final table is generated but not executed. This is a good way to change the final relation types or to customize the data ingestion.Now, we will ingest the CSV file into the Vertica database.
read_csv( path = "titanic_subset.csv", table_name = "titanic_subset", schema = "public", quotechar = '"', sep = ",", na_rep = "", )
123pclass123survivedAbcnameAbcsex123age123sibsp123parchAbcticket123fareAbccabinAbcembarked123boat123bodyAbchome.dest1 1 0 Blackwell, Mr. Stephen Weart male 45.0 0 0 113784 35.5 T S [null] [null] Trenton, NJ 2 1 0 Clark, Mr. Walter Miller male 27.0 1 0 13508 136.7792 C89 C [null] [null] Los Angeles, CA 3 1 0 Davidson, Mr. Thornton male 31.0 1 0 F.C. 12750 52.0 B71 S [null] [null] Montreal, PQ 4 1 0 Head, Mr. Christopher male 42.0 0 0 113038 42.5 B11 S [null] [null] London / Middlesex 5 1 0 Long, Mr. Milton Clyde male 29.0 0 0 113501 30.0 D6 S [null] 126 Springfield, MA 6 1 0 Compton, Mr. Alexander Taylor Jr male 37.0 1 1 PC 17756 83.1583 E52 C [null] [null] Lakewood, NJ 7 1 0 Evans, Miss. Edith Corse female 36.0 0 0 PC 17531 31.6792 A29 C [null] [null] New York, NY 8 1 0 Harris, Mr. Henry Birkhardt male 45.0 1 0 36973 83.475 C83 S [null] [null] New York, NY 9 1 0 McCarthy, Mr. Timothy J male 54.0 0 0 17463 51.8625 E46 S [null] 175 Dorchester, MA 10 1 0 Cairns, Mr. Alexander male [null] 0 0 113798 31.0 [null] S [null] [null] [null] 11 1 0 Douglas, Mr. Walter Donald male 50.0 1 0 PC 17761 106.425 C86 C [null] 62 Deephaven, MN / Cedar Rapids, IA 12 1 0 Giglio, Mr. Victor male 24.0 0 0 PC 17593 79.2 B86 C [null] [null] [null] 13 1 0 Hilliard, Mr. Herbert Henry male [null] 0 0 17463 51.8625 E46 S [null] [null] Brighton, MA 14 1 0 Artagaveytia, Mr. Ramon male 71.0 0 0 PC 17609 49.5042 [null] C [null] 22 Montevideo, Uruguay 15 1 0 Carrau, Mr. Jose Pedro male 17.0 0 0 113059 47.1 [null] S [null] [null] Montevideo, Uruguay 16 1 0 Futrelle, Mr. Jacques Heath male 37.0 1 0 113803 53.1 C123 S [null] [null] Scituate, MA 17 1 0 Harrison, Mr. William male 40.0 0 0 112059 0.0 B94 S [null] 110 [null] 18 1 0 Holverson, Mr. Alexander Oskar male 42.0 1 0 113789 52.0 [null] S [null] 38 New York, NY 19 1 0 Hoyt, Mr. William Fisher male [null] 0 0 PC 17600 30.6958 [null] C 14 [null] New York, NY 20 1 0 McCaffry, Mr. Thomas Francis male 46.0 0 0 13050 75.2417 C6 C [null] 292 Vancouver, BC Rows: 20 | Columns: 14Important
A limited number of rows, determined by the
parse_nrowsparameter, is ingested. If your dataset is large and you want to ingest the entire dataset, increase its value.Let’s specify data types using
dtypeparameter.read_csv( path = "titanic_subset.csv", table_name = "titanic_sub_dtypes", schema = "public", quotechar = '"', sep = ",", na_rep = "", dtype = { "pclass": "Integer", "survived": "Integer", "name": "Varchar(164)", "sex": "Varchar(20)", "age": "Numeric(6,3)", "sibsp": "Integer", "parch": "Integer", "ticket": "Varchar(36)", "fare": "Numeric(10,5)", "cabin": "Varchar(30)", "embarked": "Varchar(20)", "boat": "Varchar(100)", "body": "Integer", "home.dest": "Varchar(100)", }, )
123pclass123survivedAbcnameAbcsex123age123sibsp123parchAbcticket123fareAbccabinAbcembarkedAbcboat123bodyAbchome.dest1 1 0 Artagaveytia, Mr. Ramon male 71.0 0 0 PC 17609 49.5042 [null] C [null] 22 Montevideo, Uruguay 2 1 0 Blackwell, Mr. Stephen Weart male 45.0 0 0 113784 35.5 T S [null] [null] Trenton, NJ 3 1 0 Cairns, Mr. Alexander male [null] 0 0 113798 31.0 [null] S [null] [null] [null] 4 1 0 Carrau, Mr. Jose Pedro male 17.0 0 0 113059 47.1 [null] S [null] [null] Montevideo, Uruguay 5 1 0 Clark, Mr. Walter Miller male 27.0 1 0 13508 136.7792 C89 C [null] [null] Los Angeles, CA 6 1 0 Compton, Mr. Alexander Taylor Jr male 37.0 1 1 PC 17756 83.1583 E52 C [null] [null] Lakewood, NJ 7 1 0 Davidson, Mr. Thornton male 31.0 1 0 F.C. 12750 52.0 B71 S [null] [null] Montreal, PQ 8 1 0 Douglas, Mr. Walter Donald male 50.0 1 0 PC 17761 106.425 C86 C [null] 62 Deephaven, MN / Cedar Rapids, IA 9 1 0 Evans, Miss. Edith Corse female 36.0 0 0 PC 17531 31.6792 A29 C [null] [null] New York, NY 10 1 0 Futrelle, Mr. Jacques Heath male 37.0 1 0 113803 53.1 C123 S [null] [null] Scituate, MA 11 1 0 Giglio, Mr. Victor male 24.0 0 0 PC 17593 79.2 B86 C [null] [null] [null] 12 1 0 Harris, Mr. Henry Birkhardt male 45.0 1 0 36973 83.475 C83 S [null] [null] New York, NY 13 1 0 Harrison, Mr. William male 40.0 0 0 112059 0.0 B94 S [null] 110 [null] 14 1 0 Head, Mr. Christopher male 42.0 0 0 113038 42.5 B11 S [null] [null] London / Middlesex 15 1 0 Hilliard, Mr. Herbert Henry male [null] 0 0 17463 51.8625 E46 S [null] [null] Brighton, MA 16 1 0 Holverson, Mr. Alexander Oskar male 42.0 1 0 113789 52.0 [null] S [null] 38 New York, NY 17 1 0 Hoyt, Mr. William Fisher male [null] 0 0 PC 17600 30.6958 [null] C 14 [null] New York, NY 18 1 0 Long, Mr. Milton Clyde male 29.0 0 0 113501 30.0 D6 S [null] 126 Springfield, MA 19 1 0 McCaffry, Mr. Thomas Francis male 46.0 0 0 13050 75.2417 C6 C [null] 292 Vancouver, BC 20 1 0 McCarthy, Mr. Timothy J male 54.0 0 0 17463 51.8625 E46 S [null] 175 Dorchester, MA Rows: 20 | Columns: 14Note
You can ingest multiple CSV files into the Vertica database by using the following syntax.
read_csv( path = "*.csv", table_name = "titanic_multi_files", schema = "public", quotechar = '"', sep = ",", na_rep = "", )
Note
The
read_csv()function offers various additional parameters and options. Check the documentation to explore its capabilities, such as the ability to automatically guess the separator or ingest a specific number of rows.See also
read_json(): Ingests a JSON file into the Vertica DB.