The SQL INSERT statement is used to insert data into a table. The steps include: specify the target table to list the columns to be inserted. Specify the value to be inserted (the order of values must correspond to the column name)
SQL INSERT statement
The SQL INSERT statement is used to insert data into a table. Its syntax is as follows:
<code>INSERT INTO table_name (column1, column2, ...) VALUES (value1, value2, ...)</code>
The following are the steps to use the INSERT statement:
- Specify the target table: Use the
INTO
keyword to specify the table to insert data. - List the columns to be inserted: List the column names of the values to be inserted in brackets.
- Specified value: Lists the values to be inserted into the specified column in parentheses. The order of values must correspond to the order of column names.
Example:
Suppose we have a table called students
that contains id
, name
and age
columns. To insert a row of data into this table, we can use the following statement:
<code>INSERT INTO students (id, name, age) VALUES (1, 'John', 21)</code>
Notes on INSERT statements:
- The inserted value must be compatible with the column's data type.
- If no columns to be inserted are specified, the value is inserted into all columns in the table.
- If the value to be inserted contains special characters (such as single quotes), you must use escape characters (\).
- You can use the
DEFAULT
keyword to insert the default value if the column has the default value. - You can use a subquery or a SELECT statement in an INSERT statement to insert complex data.
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