the min and max values of each block are stored and can be accessed directly without iterating the data every time a query executes. During this process some metadata is also generated, e.g. These columns are being used as data is loaded into the table to sort it accordingly. The default setting is No.When you create a table, you can optionally define one or more columns as sort keys. Strip Outer Array Select (JSON only) Strips the outer array from the JSON file, enabling JSON files that contain a single, anonymous array to be loaded without error. Skip Header Rows Integer The number of rows at the top of the file to skip. Line Terminator Text (TEXTFILE only) The delimiter to be used that separates records (rows) in the file. Field Terminator Text (TEXTFILE only) The delimiter to be used that separates fields (columns) in the file. Format Select Choose a format for the source file. The Matillion ETL instance must have access to this data (typically, access is granted according to the AWS credentials on the instance, or if the bucket is public). Location Select The Amazon S3 bucket location for the external table data. When creating partitioned data using the Add Partition Component, it is vital that those partitioned columns have already been marked using this property. For example, it is common for a date column to be chosen as a partition column, thus storing all other data according to the date it belongs to. When a partition is created, values for that column become distinct Amazon S3 storage locations, allowing rows of data in a location that is dependent on their partition column value. Partition columns allow queries on large datasets to be optimized when that query is made against the columns chosen as partition columns. Partition Select Multiple Mark one or more columns in this table as potential partitions. Table Metadata (Nested) Checkbox When the Define Nested Metadata checkbox is ticked inside the Table Metadata property, a tree structure can be defined for metadata. Decimal Places Relevant only for numeric, it is the maximum number of digits that may appear to the right of the decimal point. For Amazon Redshift, since all data is stored using UTF-8, any non-ASCII character will count as 2 or more bytes.įor numeric types, this is the total number of digits allowed, whether before or after the decimal point. This is a limit on the number of bytes, not characters. Size For text types, this is the maximum length. ![]() ![]() More.ĭateTime: This type is suitable for dates, times, or timestamps (both date and time). More.ĭate: This type is suitable for dates without times. More.īoolean: This type is suitable for data that is either true or false. Numeric: This type is suitable for numeric types, without or with decimals. Integer: This type is suitable for whole-number types (no decimals). Table Metadata Column Name The name of the new column Data Type Text: This type can hold any type of data, subject to a maximum size. cascade is used, which may actually remove many other database objects. Note: Since other database objects may depend upon this table, drop. This guarantees that after the component succeeds, the table matches the schema defined in this component however, any existing data in an existing table will be lost. ![]() Replace: This drops any existing table of the same name, and then creates a new table. If the schema of the existing table does not match the schema defined in this component, no attempt is made to fix or correct it, which could lead to errors later in the job if you did not expect an existing table to exist, or to have a different schema to the one defined in this component. This is the default setting.Ĭreate if not exists: This will only create a new table if a table of the same name does not already exist. This will generate an error if a table with the same name already exists, but will never destroy existing data. Create/Replace Select Create: Creates a new table. New Table Name Text The name of the table to create or replace. The special value,, will use the schema defined in the environment.įor more information about using multiple schemas, read Schemas. To learn more about external schemas, read 'Configuring The Matillion ETL Client' from Getting Started With Amazon Redshift Spectrum documentation. External tables require external schemas and regular schemas will not work. Properties Redshift Properties Property Setting Description Name Text A human-readable name for the component. Nested data loads from JSON or Parquet file formats may also be set up using this component via the Define Nested Metadata checkbox in the Table Metadata property.
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