Interface

PreparedSQLStatement

Description

Provides the API for working with prepared statements. Use Database.Prepare to create a PreparedSQLStatement.

Methods

Name

Parameters

Returns

Shared

Bind

zeroBasedParam As Integer, value As Variant

BindType

zeroBasedIndex As Integer, type As Integer

ExecuteSQL

ParamArray bindValues() As Variant

SelectSQL

ParamArray bindValues() As Variant

RowSet

Method descriptions

PreparedSQLStatement.Bind

Bind(zeroBasedParam As Integer, value As Variant)

Binds a value and its type for the prepared statement.

Use Database.Prepare to set up the bind.

This example creates a SQLite prepared statement to retrieve data from a Customers table. It then displays the data in a Listbox:

Var stmt As SQLitePreparedStatement

// note in a prepared statement you DO NOT put in the quotes
stmt = SQLitePreparedStatement(db.Prepare("SELECT * FROM Customers WHERE FirstName like ? "))

// have to tell sqlite what types the items being bound are so it does the right thing
stmt.BindType(0, SQLitePreparedStatement.SQLITE_TEXT)
stmt.Bind(0, TextField1.Text)

// perform the search
Var rs As RowSet = stmt.SQLSelect

ListBox1.RemoveAllRows
ListBox1.ColumnCount = rs.ColumnCount
ListBox1.HasHeader = True

Var hasHeadings As Boolean

While rs.AfterLastRow <> True
  ListBox1.AddRow("")

  For i As Integer = 0 To rs.ColumnCount-1
    If Not hasHeadings Then ListBox1.HeaderAt(i) = rs.ColumnAt(i+1).Name
    ListBox1.CellTextAt(ListBox1.LastAddedRowIndex, i) = rs.ColumnAt(i+1).StringValue
  Next

  rs.MoveToNextRow
  hasHeadings = True
Wend

PreparedSQLStatement.BindType

BindType(zeroBasedIndex As Integer, type As Integer)

Specify types for multiple bind values. Each Database plug-in will have its own values.

PreparedSQLStatement.ExecuteSQL

ExecuteSQL(ParamArray bindValues() As Variant)

Same as SelectSQL but does not return a result set. Executes and returns the result set of the prepared statement.

BindValues is optional and is intended for convenience only. If bindValues is not empty, ExecuteSQL will use the passed in values instead of the ones specified by calling Bind.

PreparedSQLStatement.SelectSQL

SelectSQL(ParamArray bindValues() As Variant) As RowSet

Executes and returns the result set of the prepared statement.

The bindValues parameter is optional and is intended for convenience only. If bindValues is not empty SelectSQL will use the passed in values instead of the ones specified by calling Bind.

Notes

Database.SelectSQL and Database.ExecuteSQL both support prepared statements without the need to use any of the prepared statement classes. These cover most cases.

The reasons for using the prepared statement classes are:

  • When using an uncommon column type that is likely unique to a particular database server. In that case, Database.SelectSQL and Database.ExecuteSQL may not function properly and your only choice would be to use the appropriate prepared statement class.

  • When repeatedly calling the same SQL statement in a loop. Using prepared statements in this case will increase performance as the prepared statement won't need to be recreated each time as is the case with Database.SelectSQL and Database.ExecuteSQL.

You do not typically need to work directly with this interface. Instead use the appropriate PreparedStatement class for the database you are using:

Compatibility

All project types on all supported operating systems.