You signed in with another tab or window. Reload to refresh your session.You signed out in another tab or window. Reload to refresh your session.You switched accounts on another tab or window. Reload to refresh your session.Dismiss alert
Copy file name to clipboardExpand all lines: articles/synapse-analytics/sql/develop-openrowset.md
+5-5Lines changed: 5 additions & 5 deletions
Display the source diff
Display the rich diff
Original file line number
Diff line number
Diff line change
@@ -239,19 +239,19 @@ CSV parser version 2.0 specifics:
239
239
240
240
HEADER_ROW = { TRUE | FALSE }
241
241
242
-
Specifies whether CSV file contains header row. Default is FALSE. Supported in PARSER_VERSION='2.0'. If TRUE, column names will be read from first row according to FIRSTROW argument. If TRUE and schema is specified using WITH, binding of column names will be done by column name, not ordinal positions.
242
+
Specifies whether a CSV file contains header row. Default is `FALSE.` Supported in PARSER_VERSION='2.0'. If TRUE, the column names will be read from the first row according to FIRSTROW argument. If TRUE and schema is specified using WITH, binding of column names will be done by column name, not ordinal positions.
243
243
244
244
DATAFILETYPE = { 'char' | 'widechar' }
245
245
246
-
Specifies encoding: char is used for UTF8, widechar is used for UTF16 files.
246
+
Specifies encoding: `char` is used for UTF8, `widechar` is used for UTF16 files.
Specifies the code page of the data in the data file. The default value is 65001 (UTF-8 encoding). See more details about this option [here](/sql/t-sql/functions/openrowset-transact-sql?view=sql-server-ver15&preserve-view=true#codepage).
This option will disable the file modification check during the query execution, and read the files that are updated while the query is running. This is usefull option when you need to read append-only files that are appended while the query is running. In the appendable files, the existing content is not updated, and only new rows are added. Therefore, the probability of wrong results is minimized compared to the updateable files. This option might enable you to read the frequently appended files without handling the errors. See more information in [querying appendable CSV files](query-single-csv-file.md#querying-appendable-files) section.
254
+
This option will disable the file modification check during the query execution, and read the files that are updated while the query is running. This is useful option when you need to read append-only files that are appended while the query is running. In the appendable files, the existing content is not updated, and only new rows are added. Therefore, the probability of wrong results is minimized compared to the updateable files. This option might enable you to read the frequently appended files without handling the errors. See more information in [querying appendable CSV files](query-single-csv-file.md#querying-appendable-files) section.
255
255
256
256
## Fast delimited text parsing
257
257
@@ -261,9 +261,9 @@ There are two delimited text parser versions you can use. CSV parser version 1.0
261
261
262
262
You can easily query both CSV and Parquet files without knowing or specifying schema by omitting WITH clause. Column names and data types will be inferred from files.
263
263
264
-
Parquet files contain column metadata which will be read, type mappings can be found in [type mappings for Parquet](#type-mapping-for-parquet). Check [reading Parquet files without specifying schema](#read-parquet-files-without-specifying-schema) for samples.
264
+
Parquet files contain column metadata, which will be read, type mappings can be found in [type mappings for Parquet](#type-mapping-for-parquet). Check [reading Parquet files without specifying schema](#read-parquet-files-without-specifying-schema) for samples.
265
265
266
-
For CSV files column names can be read from header row. You can specify whether header row exists using HEADER_ROW argument. If HEADER_ROW = FALSE, generic column names will be used: C1, C2, ... Cn where n is number of columns in file. Data types will be inferred from first 100 data rows. Check [reading CSV files without specifying schema](#read-csv-files-without-specifying-schema) for samples.
266
+
For the CSV files, column names can be read from header row. You can specify whether header row exists using HEADER_ROW argument. If HEADER_ROW = FALSE, generic column names will be used: C1, C2, ... Cn where n is number of columns in file. Data types will be inferred from first 100 data rows. Check [reading CSV files without specifying schema](#read-csv-files-without-specifying-schema) for samples.
267
267
268
268
> [!IMPORTANT]
269
269
> There are cases when appropriate data type cannot be inferred due to lack of information and larger data type will be used instead. This brings performance overhead and is particularly important for character columns which will be inferred as varchar(8000). For optimal performance, please [check inferred data types](./best-practices-serverless-sql-pool.md#check-inferred-data-types) and [use appropriate data types](./best-practices-serverless-sql-pool.md#use-appropriate-data-types).
0 commit comments