Cannot get simple PostgreSQL insert to work

Property misevaluation: single vs double quotes

String literals vs identifiers

The strategic placement of quotation marks in PostgreSQL can make or break your SQL statement. Single quotes are used for string literals, and double quotes are for identifiers.

-- Single quotes: 'value1'
-- Double quotes: "column1"
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Identifiers and case sensitivity

In PostgreSQL, case sensitivity matters, especially with identifiers. By default, PostgreSQL converts all unquoted identifiers to lowercase. To avoid this, use lowercase consistently or brace yourself for a whirlwind of double-quoting.

-- This is right but can be stressful
INSERT INTO "YourTable" ("YourColumn") VALUES ('yourValue');

-- This is just easy 
INSERT INTO yourtable (yourcolumn) VALUES ('yourvalue');
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The unseen: auto-increment columns and constraints

Dealing with auto-increment columns

Columns with auto-increment values, often id fields, are automatically filled by PostgreSQL. There's no need to state them explicitly in your INSERT statement.

-- If id is auto-increment, why bother?
-- Let PostgreSQL do the heavy lifting
INSERT INTO yourtable (other_column1, other_column2) VALUES ('value1', 'value2');
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Understanding constraints

In addition to column types and names, PostgreSQL imposes constraints on the values that can be inserted. Be aware of not-null and unique constraints, as well as foreign key restrictions.

Error messages: a lifeline, not a death sentence

INSERT errors aren't the end! The error messages are there to help. There could be a data type misalignment, a missing column, or a constraint violation.

Handling those quirky PostgreSQL inserts

Reserved keywords and mixed case nightmares

Employing mixed case or reserved_keyword identifiers can become a source of stressful bug hunting. Remember, when unquoted, PostgreSQL, like a stubborn mule, converts all to lowercase.

Default blues

When a column comes with a default value, stating "DEFAULT" in the insert statement can be as redundant as a back-up parachute. On the other hand, omitting it when required will surely cause you a syntax error.

Tips for trivial PostgreSQL inserts

Naming etiquette

Consider sticking to lowercase identifiers to evade the headache of consistently double-quoting identifiers.

-- Because nobody likes to carry extra baggage!
INSERT INTO chewbacca (hansolo, princessleia) VALUES ('Millennium Falcon', 'Alderaan');
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Default duty

Omitting default values in your insert statement is a good practice. Less mess, fewer stress!

-- Here PostgreSQL, fill the blanks yourself!
INSERT INTO droids (r2d2) VALUES ('blueprints');
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