DELETE

Table of contents

1. Overview
2. Multiple conditions
3. IN / NOT IN
4. BETWEEN
5. Dialect-aware delete (LIMIT support)
6. RETURNING (PostgreSQL)
7. Method reference

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Overview

DeleteBuilder builds parameterized DELETE FROM … WHERE statements:

import com.github.ezframework.javaquerybuilder.query.builder.QueryBuilder;
import com.github.ezframework.javaquerybuilder.query.sql.SqlResult;

SqlResult result = QueryBuilder.deleteFrom("sessions")
    .whereEquals("user_id", 99)
    .build();

// → DELETE FROM sessions WHERE user_id = ?
// Parameters: [99]

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Multiple conditions

SqlResult result = QueryBuilder.deleteFrom("logs")
    .whereLessThan("created_at", "2025-01-01")
    .whereEquals("level", "debug")
    .build();
// → DELETE FROM logs WHERE created_at < ? AND level = ?

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IN / NOT IN

SqlResult result = QueryBuilder.deleteFrom("users")
    .whereIn("status", List.of("banned", "deleted"))
    .build();
// → DELETE FROM users WHERE status IN (?, ?)

SqlResult result2 = QueryBuilder.deleteFrom("products")
    .whereNotIn("category", List.of("archive", "draft"))
    .build();
// → DELETE FROM products WHERE category NOT IN (?, ?)

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BETWEEN

SqlResult result = QueryBuilder.deleteFrom("events")
    .whereBetween("score", 0, 10)
    .build();
// → DELETE FROM events WHERE score BETWEEN ? AND ?

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Dialect-aware delete (LIMIT support)

MySQL and SQLite support a LIMIT clause on DELETE. Pass a Query built with a limit() call to renderDelete on the appropriate dialect:

Query q = new QueryBuilder()
    .from("logs")
    .whereLessThan("age", 30)
    .limit(100)
    .build();

// MySQL — LIMIT honored, back-tick quoting applied
SqlResult mysql = SqlDialect.MYSQL.renderDelete(q);
// → DELETE FROM `logs` WHERE `age` < ? LIMIT 100

// SQLite — LIMIT honored, double-quote quoting applied
SqlResult sqlite = SqlDialect.SQLITE.renderDelete(q);
// → DELETE FROM "logs" WHERE "age" < ? LIMIT 100

// STANDARD — LIMIT dropped
SqlResult std = SqlDialect.STANDARD.renderDelete(q);
// → DELETE FROM logs WHERE age < ?

Alternatively, use DeleteBuilder.build(SqlDialect) which also calls renderDelete internally:

SqlResult result = QueryBuilder.deleteFrom("logs")
    .whereLessThan("age", 30)
    .build(SqlDialect.MYSQL);
// → DELETE FROM `logs` WHERE `age` < ?
// (limit requires a Query built via QueryBuilder.build().limit())

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RETURNING (PostgreSQL)

RETURNING on DELETE is rendered by the dialect — it is appended only when SqlDialect.POSTGRESQL (or a dialect that overrides supportsReturning()) is used.

SqlResult result = QueryBuilder.deleteFrom("users")
    .whereEquals("id", 99)
    .returning("id", "email")
    .build(SqlDialect.POSTGRESQL);

// → DELETE FROM "users" WHERE "id" = ? RETURNING id, email
// Parameters: [99]

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Method reference

Method	Returns	Description
from(String table)	DeleteBuilder	Set target table
whereEquals(col, val)	DeleteBuilder	WHERE col = ? (AND)
whereNotEquals(col, val)	DeleteBuilder	WHERE col != ? (AND)
whereGreaterThan(col, val)	DeleteBuilder	WHERE col > ? (AND)
whereGreaterThanOrEquals(col, val)	DeleteBuilder	WHERE col >= ? (AND)
whereLessThan(col, val)	DeleteBuilder	WHERE col < ? (AND)
whereLessThanOrEquals(col, val)	DeleteBuilder	WHERE col <= ? (AND)
whereIn(col, List<?>)	DeleteBuilder	WHERE col IN (...) (AND)
whereNotIn(col, List<?>)	DeleteBuilder	WHERE col NOT IN (...) (AND)
whereBetween(col, from, to)	DeleteBuilder	WHERE col BETWEEN ? AND ? (AND)
returning(String... cols)	DeleteBuilder	Append RETURNING col1, col2, ... (PostgreSQL only; use with SqlDialect.POSTGRESQL)
build()	SqlResult	Render with standard dialect
build(SqlDialect dialect)	SqlResult	Render with specified dialect