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Level: Intermediate |
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Familiarity with VFP, DBC, Views |
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What is Client-Server? |
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Why Client-Server? |
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Why NOT Client-Server? |
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How? ODBC/SPT/Views |
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Advanced Techniques |
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Learning More |
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Two separate processes |
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Same or different machines |
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Bandwidth |
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VFP is designed for LANs |
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Data size |
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VFP limited to 2 Gb file size |
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Security |
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VFP tables can be read by anyone |
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Resource Constraints |
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Programmer skill & training |
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Need for on-going DBA maintenance |
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Infrastructure stability |
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Performance |
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Rushmore is still king |
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Hardware can solve this |
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Connectivity - DSNs & Connections |
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Two Paths: SPT & Views |
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SPT: Manual, full control |
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Views: GUI, simpler, limited |
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ODBC Data Set Names (DSN) |
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SQLConnect() |
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SQLStringConnect() |
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DBC-defined Connections |
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CREATE, DELETE, MODIFY, RENAME, DISPLAY
CONNECTION |
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Beware: Share Connections |
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Transactions are at the connection level |
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Create graphically or programmatically: |
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CREATE, DELETE, MODIFY, RENAME, DISPLAY VIEW |
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Utility Functions: SQLTABLES(), SQLCOLUMNS() |
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Connection functions, already covered |
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SQLExec() passes commands to the server, via ODBC |
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SQLCOMMIT(), SQLROLLBACK() completes
transactions |
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SQLGetProp, SQLSetProp() |
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works on Connections |
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DBGetProp(), DBSetProp() |
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works on DBC - persistent |
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CursorSetProp(), CursorGetProp() |
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works on open cursors |
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SQL can be: |
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Batched |
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Fetched progressively |
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Precompiled |
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Requires a separate connection |
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Start with ODBC against FoxPro |
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Server “Lite” available from most vendors |
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Use ODBC DSNs, Views |
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Use GenDBC to see how commands & functions
work |
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Start with automatic transactions |
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What? Two separate processes |
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Why? |
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Bandwidth |
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Data Size |
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Security |
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Why Not? |
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Resource constraints |
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How? Carefully! |
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Notes