In SQL, data import can be implemented in two ways: INSERT statement: insert data line by line, syntax is INSERT INTO table_name (column1, ...) VALUES (value1, ...). BULK INSERT: Quick batch import data from a file or database, syntax BULK INSERT table_name FROM 'file_path' WITH (FIELDTERMINATOR = ',', ROWTERMINATOR = '\n', FIRSTROW = 1).
How to import data into a database
Importing data is the process of loading external data into a database and can provide data for analysis, processing, or storage purposes. In SQL, there are many ways to import data. Here we will introduce the two most commonly used methods:
INSERT statement
The INSERT statement allows you to insert single or multiple records into a table. The syntax is as follows:
<code class="sql">INSERT INTO table_name (column1, column2, ...) VALUES (value1, value2, ...);</code>
For example, the following statement inserts two records into a table named customers
:
<code class="sql">INSERT INTO customers (name, email, address) VALUES ('John Doe', 'john.doe@example.com', '123 Main Street'); INSERT INTO customers (name, email, address) VALUES ('Jane Doe', 'jane.doe@example.com', '456 Elm Street');</code>
BULK INSERT
BULK INSERT is a more efficient way to quickly import large amounts of data (usually from files or other databases) into tables. The syntax is as follows:
<code class="sql">BULK INSERT table_name FROM 'file_path' WITH ( FIELDTERMINATOR = ',', ROWTERMINATOR = '\n', FIRSTROW = 1 );</code>
in:
-
file_path
is the data file path to import -
FIELDTERMINATOR
is a character that separates data from each column (such as a comma or tab character) -
ROWTERMINATOR
is a character that separates each line (usually a newline) -
FIRSTROW
specifies the number of rows to skip (such as the title row)
For example, the following statement imports data from a file named data.csv
into the customers
table, where a comma is used as the field separator, a newline is used as the line separator, and the first line contains the title:
<code class="sql">BULK INSERT customers FROM 'data.csv' WITH ( FIELDTERMINATOR = ',', ROWTERMINATOR = '\n', FIRSTROW = 1 );</code>
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