How Do I Escape Apostrophes in SQL INSERT and SELECT Statements?

Handling Apostrophes in SQL Data Insertion

Inserting data containing apostrophes directly into a SQL database can lead to errors. The apostrophe, acting as a string delimiter, can prematurely terminate the string. To avoid this, you must escape the apostrophe within your SQL query.

Correct Method:

<code class="language-sql">INSERT INTO Person (First, Last) VALUES ('Joe', 'O''Brien');</code>

Notice how the apostrophe within "O'Brien" is escaped by doubling it (''). This clearly indicates to the database that it's part of the string, not a delimiter.

Apostrophe Handling in SELECT Statements:

The same escaping technique applies to SELECT queries:

<code class="language-sql">SELECT First, Last FROM Person WHERE Last = 'O''Brien';</code>

Why Escape?

The apostrophe's role as a string boundary in SQL necessitates escaping. Doubling it ensures the database correctly interprets it as data, preventing premature string termination.

Automated Escaping in Programming:

Directly manipulating SQL with raw queries requires manual apostrophe escaping. However, most programming languages and database frameworks offer built-in functions to automatically handle escaping, preventing SQL injection vulnerabilities. Using these functions is strongly recommended.

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